在 Android 15 的初始版本的基础上，我们会继续更新该平台，不断修复问题和改进性能，然后向受支持的设备发布这些修复和改进。这些更新通过季度平台版本 (QPR) 每季度发布一次，作为功能更新的一部分提供给 AOSP 和 Google Pixel 设备。
虽然这些更新不包含影响应用的 API 变更，但我们仍会提供最新 QPR Beta 版 build 的映像，以便您根据需要使用这些 build 来测试您的应用（例如，如果有即将推出的功能可能会影响应用的用户体验）。
如需查找适用于已经发布的该平台稳定版本的 OTA 映像，请参阅适用于 Nexus 和 Pixel 设备的完整 OTA 映像。
应用 OTA 映像可帮助您恢复接收了 Android 15 QPR Beta 版 build 的 OTA 更新但安装更新后无法启动的设备。如果您尝试在设备上获取 Android 15 QPR1 但不打算从失败的 OTA 更新恢复，请参阅获取 Android 15 QPR Beta 版 build。
OTA 映像适用于以下 Pixel 设备：
- Pixel 6 和 Pixel 6 Pro
- Pixel 6a
- Pixel 7 和 Pixel 7 Pro
- Pixel 7a
- Pixel Fold
- Pixel Tablet
- Pixel 8 和 Pixel 8 Pro
- Pixel 8a
- Pixel 9、Pixel 9 Pro、Pixel 9 Pro XL 和 Pixel 9 Pro Fold
将 Beta 版 build 安装到 Pixel 设备后，您的设备会自动注册适用于 Pixel 的 Android Beta 版计划，并通过持续无线下载 (OTA) 更新至最新的 Beta 版 build（包括 QPR），直到您选择在该计划中取消注册相应设备。我们还将在每个里程碑提供可刷写的映像，因此您可以选择最适合自己的测试环境的方法。
使用以下链接和说明将受支持的设备更新到最新版本。如需寻求其他方式来获取适用于测试和开发的 QPR1，请参阅获取 Android 15 QPR Beta 版 build。
应用 OTA 映像
从下表中下载 OTA 设备映像，然后按照适用于 Nexus 和 Pixel 设备的完整 OTA 映像中列出的更新说明进行应用。
您可以随时选择还原为最新的公开版 build。
设备 OTA 映像
| 发布日期 | 2024 年 11 月 22 日 |
| build | AP41.240925.012 |
| 模拟器支持 | x86（64 位）、ARM (v8-A) |
| 安全补丁级别 | 2024 年 11 月 |
| Google Play 服务 | 24.34.33 |
| 设备 | 下载链接和 SHA-256 校验和 |
|---|---|
| Pixel 6 |
a4c65573f20cdc962a9808277595cbbb7d1890e057039fce5b7273fbcc047c1a |
| Pixel 6 Pro |
d609a7d535b6172a9eb68c1c2f5de616922417ac3686bef5bc188bf2ec992187 |
| Pixel 6a |
3bd3f979619709f2553f549a5a0e608b9898e229cda1acfe783587fb63825ce8 |
| Pixel 7 |
e8b94b088394e687ea9ad2f1455999ab4f4026fabfd12af2cfabd57c7865910a |
| Pixel 7 Pro |
381b1ad508e8e86d5b0077a750eebeeb5877a9b1d71e70d80b4c675e7c3e7269 |
| Pixel 7a |
ec1c61453f6c9a32c6c79762dd59398e42ada6913216caeb7e752c3ac6e7bc1b |
| Pixel Fold |
24fa6c710a2d34dc5e724d697d992468233a1dc84bbf67cd6cf3287930b23562 |
| Pixel Tablet |
92a5985b5f9fb71806b72d766bd617376d5ba3d8d78ca8b9605149a09eb5111f |
| Pixel 8 |
ce50c9abbd1e9cc4ea13e81c3b6ac47c0500c85431f43e826da8c4c414a9fcf4 |
| Pixel 8 Pro |
54193ffb73584e6cc190fba30072cb9ed0f1184d8a04a4a23312c7647b77c03a |
| Pixel 8a |
dabb492d77378167420ef2a4e882851e66123015c58b626bbc59241ec8a295d9 |
| Pixel 9 |
d8bdb9c3c3d9c6dfd9465f2cd49cd93efb62f571d38da92e871f96903ffd899b |
| Pixel 9 Pro |
ffe0f6af0c71eb0764082118dc034f9ab6b46c378d5ca0bc96a8421a2ec73a24 |
| Pixel 9 Pro XL |
4149d9d5dab70baf7b02d46b8b7bddd582a1178f7629a06d52ef704d9c1de5c4 |
| Pixel 9 Pro Fold |
78c9de744cee37213ab15b7d89962e748ca4d22f615dff25603b50afdc5e60f6 |
还原为公开版 build
您可以使用 Android 刷写工具刷入出厂映像，也可以从适用于 Nexus 和 Pixel 设备的出厂映像页面获取出厂规格系统映像，然后手动将其刷入设备。
Download Android 15 OTA system image
Before downloading, you must agree to the following terms and conditions.
Terms and Conditions
By clicking to accept, you hereby agree to the following:All use of this development version SDK will be governed by the Android Software Development Kit License Agreement (available at https://developer.android.com/studio/terms and such URL may be updated or changed by Google from time to time), which will terminate when Google issues a final release version.
Your testing and feedback are important part of the development process and by using the SDK, you acknowledge that (i) implementation of some features are still under development, (ii) you should not rely on the SDK having the full functionality of a stable release; (iii) you agree not to publicly distribute or ship any application using this SDK as this SDK will no longer be supported after the official Android SDK is released; and (iv) you agree that Google may deliver elements of the SDK to your devices via auto-update (OTA or otherwise, in each case as determined by Google).
WITHOUT LIMITING SECTION 10 OF THE ANDROID SOFTWARE DEVELOPMENT KIT LICENSE AGREEMENT, YOU UNDERSTAND THAT A DEVELOPMENT VERSION OF A SDK IS NOT A STABLE RELEASE AND MAY CONTAIN ERRORS, DEFECTS AND SECURITY VULNERABILITIES THAT CAN RESULT IN SIGNIFICANT DAMAGE, INCLUDING THE COMPLETE, IRRECOVERABLE LOSS OF USE OF YOUR COMPUTER SYSTEM OR OTHER DEVICE.
Download Android 15 OTA system image
Before downloading, you must agree to the following terms and conditions.
Terms and Conditions
By clicking to accept, you hereby agree to the following:All use of this development version SDK will be governed by the Android Software Development Kit License Agreement (available at https://developer.android.com/studio/terms and such URL may be updated or changed by Google from time to time), which will terminate when Google issues a final release version.
Your testing and feedback are important part of the development process and by using the SDK, you acknowledge that (i) implementation of some features are still under development, (ii) you should not rely on the SDK having the full functionality of a stable release; (iii) you agree not to publicly distribute or ship any application using this SDK as this SDK will no longer be supported after the official Android SDK is released; and (iv) you agree that Google may deliver elements of the SDK to your devices via auto-update (OTA or otherwise, in each case as determined by Google).
WITHOUT LIMITING SECTION 10 OF THE ANDROID SOFTWARE DEVELOPMENT KIT LICENSE AGREEMENT, YOU UNDERSTAND THAT A DEVELOPMENT VERSION OF A SDK IS NOT A STABLE RELEASE AND MAY CONTAIN ERRORS, DEFECTS AND SECURITY VULNERABILITIES THAT CAN RESULT IN SIGNIFICANT DAMAGE, INCLUDING THE COMPLETE, IRRECOVERABLE LOSS OF USE OF YOUR COMPUTER SYSTEM OR OTHER DEVICE.
Download Android 15 OTA system image
Before downloading, you must agree to the following terms and conditions.
Terms and Conditions
By clicking to accept, you hereby agree to the following:All use of this development version SDK will be governed by the Android Software Development Kit License Agreement (available at https://developer.android.com/studio/terms and such URL may be updated or changed by Google from time to time), which will terminate when Google issues a final release version.
Your testing and feedback are important part of the development process and by using the SDK, you acknowledge that (i) implementation of some features are still under development, (ii) you should not rely on the SDK having the full functionality of a stable release; (iii) you agree not to publicly distribute or ship any application using this SDK as this SDK will no longer be supported after the official Android SDK is released; and (iv) you agree that Google may deliver elements of the SDK to your devices via auto-update (OTA or otherwise, in each case as determined by Google).
WITHOUT LIMITING SECTION 10 OF THE ANDROID SOFTWARE DEVELOPMENT KIT LICENSE AGREEMENT, YOU UNDERSTAND THAT A DEVELOPMENT VERSION OF A SDK IS NOT A STABLE RELEASE AND MAY CONTAIN ERRORS, DEFECTS AND SECURITY VULNERABILITIES THAT CAN RESULT IN SIGNIFICANT DAMAGE, INCLUDING THE COMPLETE, IRRECOVERABLE LOSS OF USE OF YOUR COMPUTER SYSTEM OR OTHER DEVICE.
Download Android 15 OTA system image
Before downloading, you must agree to the following terms and conditions.
Terms and Conditions
By clicking to accept, you hereby agree to the following:All use of this development version SDK will be governed by the Android Software Development Kit License Agreement (available at https://developer.android.com/studio/terms and such URL may be updated or changed by Google from time to time), which will terminate when Google issues a final release version.
Your testing and feedback are important part of the development process and by using the SDK, you acknowledge that (i) implementation of some features are still under development, (ii) you should not rely on the SDK having the full functionality of a stable release; (iii) you agree not to publicly distribute or ship any application using this SDK as this SDK will no longer be supported after the official Android SDK is released; and (iv) you agree that Google may deliver elements of the SDK to your devices via auto-update (OTA or otherwise, in each case as determined by Google).
WITHOUT LIMITING SECTION 10 OF THE ANDROID SOFTWARE DEVELOPMENT KIT LICENSE AGREEMENT, YOU UNDERSTAND THAT A DEVELOPMENT VERSION OF A SDK IS NOT A STABLE RELEASE AND MAY CONTAIN ERRORS, DEFECTS AND SECURITY VULNERABILITIES THAT CAN RESULT IN SIGNIFICANT DAMAGE, INCLUDING THE COMPLETE, IRRECOVERABLE LOSS OF USE OF YOUR COMPUTER SYSTEM OR OTHER DEVICE.
Download Android 15 OTA system image
Before downloading, you must agree to the following terms and conditions.
Terms and Conditions
By clicking to accept, you hereby agree to the following:All use of this development version SDK will be governed by the Android Software Development Kit License Agreement (available at https://developer.android.com/studio/terms and such URL may be updated or changed by Google from time to time), which will terminate when Google issues a final release version.
Your testing and feedback are important part of the development process and by using the SDK, you acknowledge that (i) implementation of some features are still under development, (ii) you should not rely on the SDK having the full functionality of a stable release; (iii) you agree not to publicly distribute or ship any application using this SDK as this SDK will no longer be supported after the official Android SDK is released; and (iv) you agree that Google may deliver elements of the SDK to your devices via auto-update (OTA or otherwise, in each case as determined by Google).
WITHOUT LIMITING SECTION 10 OF THE ANDROID SOFTWARE DEVELOPMENT KIT LICENSE AGREEMENT, YOU UNDERSTAND THAT A DEVELOPMENT VERSION OF A SDK IS NOT A STABLE RELEASE AND MAY CONTAIN ERRORS, DEFECTS AND SECURITY VULNERABILITIES THAT CAN RESULT IN SIGNIFICANT DAMAGE, INCLUDING THE COMPLETE, IRRECOVERABLE LOSS OF USE OF YOUR COMPUTER SYSTEM OR OTHER DEVICE.
Download Android 15 OTA system image
Before downloading, you must agree to the following terms and conditions.
Terms and Conditions
By clicking to accept, you hereby agree to the following:All use of this development version SDK will be governed by the Android Software Development Kit License Agreement (available at https://developer.android.com/studio/terms and such URL may be updated or changed by Google from time to time), which will terminate when Google issues a final release version.
Your testing and feedback are important part of the development process and by using the SDK, you acknowledge that (i) implementation of some features are still under development, (ii) you should not rely on the SDK having the full functionality of a stable release; (iii) you agree not to publicly distribute or ship any application using this SDK as this SDK will no longer be supported after the official Android SDK is released; and (iv) you agree that Google may deliver elements of the SDK to your devices via auto-update (OTA or otherwise, in each case as determined by Google).
WITHOUT LIMITING SECTION 10 OF THE ANDROID SOFTWARE DEVELOPMENT KIT LICENSE AGREEMENT, YOU UNDERSTAND THAT A DEVELOPMENT VERSION OF A SDK IS NOT A STABLE RELEASE AND MAY CONTAIN ERRORS, DEFECTS AND SECURITY VULNERABILITIES THAT CAN RESULT IN SIGNIFICANT DAMAGE, INCLUDING THE COMPLETE, IRRECOVERABLE LOSS OF USE OF YOUR COMPUTER SYSTEM OR OTHER DEVICE.
Download Android 15 OTA system image
Before downloading, you must agree to the following terms and conditions.
Terms and Conditions
By clicking to accept, you hereby agree to the following:All use of this development version SDK will be governed by the Android Software Development Kit License Agreement (available at https://developer.android.com/studio/terms and such URL may be updated or changed by Google from time to time), which will terminate when Google issues a final release version.
Your testing and feedback are important part of the development process and by using the SDK, you acknowledge that (i) implementation of some features are still under development, (ii) you should not rely on the SDK having the full functionality of a stable release; (iii) you agree not to publicly distribute or ship any application using this SDK as this SDK will no longer be supported after the official Android SDK is released; and (iv) you agree that Google may deliver elements of the SDK to your devices via auto-update (OTA or otherwise, in each case as determined by Google).
WITHOUT LIMITING SECTION 10 OF THE ANDROID SOFTWARE DEVELOPMENT KIT LICENSE AGREEMENT, YOU UNDERSTAND THAT A DEVELOPMENT VERSION OF A SDK IS NOT A STABLE RELEASE AND MAY CONTAIN ERRORS, DEFECTS AND SECURITY VULNERABILITIES THAT CAN RESULT IN SIGNIFICANT DAMAGE, INCLUDING THE COMPLETE, IRRECOVERABLE LOSS OF USE OF YOUR COMPUTER SYSTEM OR OTHER DEVICE.
Download Android 15 OTA system image
Before downloading, you must agree to the following terms and conditions.
Terms and Conditions
By clicking to accept, you hereby agree to the following:All use of this development version SDK will be governed by the Android Software Development Kit License Agreement (available at https://developer.android.com/studio/terms and such URL may be updated or changed by Google from time to time), which will terminate when Google issues a final release version.
Your testing and feedback are important part of the development process and by using the SDK, you acknowledge that (i) implementation of some features are still under development, (ii) you should not rely on the SDK having the full functionality of a stable release; (iii) you agree not to publicly distribute or ship any application using this SDK as this SDK will no longer be supported after the official Android SDK is released; and (iv) you agree that Google may deliver elements of the SDK to your devices via auto-update (OTA or otherwise, in each case as determined by Google).
WITHOUT LIMITING SECTION 10 OF THE ANDROID SOFTWARE DEVELOPMENT KIT LICENSE AGREEMENT, YOU UNDERSTAND THAT A DEVELOPMENT VERSION OF A SDK IS NOT A STABLE RELEASE AND MAY CONTAIN ERRORS, DEFECTS AND SECURITY VULNERABILITIES THAT CAN RESULT IN SIGNIFICANT DAMAGE, INCLUDING THE COMPLETE, IRRECOVERABLE LOSS OF USE OF YOUR COMPUTER SYSTEM OR OTHER DEVICE.
Download Android 15 OTA system image
Before downloading, you must agree to the following terms and conditions.
Terms and Conditions
By clicking to accept, you hereby agree to the following:All use of this development version SDK will be governed by the Android Software Development Kit License Agreement (available at https://developer.android.com/studio/terms and such URL may be updated or changed by Google from time to time), which will terminate when Google issues a final release version.
Your testing and feedback are important part of the development process and by using the SDK, you acknowledge that (i) implementation of some features are still under development, (ii) you should not rely on the SDK having the full functionality of a stable release; (iii) you agree not to publicly distribute or ship any application using this SDK as this SDK will no longer be supported after the official Android SDK is released; and (iv) you agree that Google may deliver elements of the SDK to your devices via auto-update (OTA or otherwise, in each case as determined by Google).
WITHOUT LIMITING SECTION 10 OF THE ANDROID SOFTWARE DEVELOPMENT KIT LICENSE AGREEMENT, YOU UNDERSTAND THAT A DEVELOPMENT VERSION OF A SDK IS NOT A STABLE RELEASE AND MAY CONTAIN ERRORS, DEFECTS AND SECURITY VULNERABILITIES THAT CAN RESULT IN SIGNIFICANT DAMAGE, INCLUDING THE COMPLETE, IRRECOVERABLE LOSS OF USE OF YOUR COMPUTER SYSTEM OR OTHER DEVICE.
Download Android 15 OTA system image
Before downloading, you must agree to the following terms and conditions.
Terms and Conditions
By clicking to accept, you hereby agree to the following:All use of this development version SDK will be governed by the Android Software Development Kit License Agreement (available at https://developer.android.com/studio/terms and such URL may be updated or changed by Google from time to time), which will terminate when Google issues a final release version.
Your testing and feedback are important part of the development process and by using the SDK, you acknowledge that (i) implementation of some features are still under development, (ii) you should not rely on the SDK having the full functionality of a stable release; (iii) you agree not to publicly distribute or ship any application using this SDK as this SDK will no longer be supported after the official Android SDK is released; and (iv) you agree that Google may deliver elements of the SDK to your devices via auto-update (OTA or otherwise, in each case as determined by Google).
WITHOUT LIMITING SECTION 10 OF THE ANDROID SOFTWARE DEVELOPMENT KIT LICENSE AGREEMENT, YOU UNDERSTAND THAT A DEVELOPMENT VERSION OF A SDK IS NOT A STABLE RELEASE AND MAY CONTAIN ERRORS, DEFECTS AND SECURITY VULNERABILITIES THAT CAN RESULT IN SIGNIFICANT DAMAGE, INCLUDING THE COMPLETE, IRRECOVERABLE LOSS OF USE OF YOUR COMPUTER SYSTEM OR OTHER DEVICE.
Download Android 15 OTA system image
Before downloading, you must agree to the following terms and conditions.
Terms and Conditions
By clicking to accept, you hereby agree to the following:All use of this development version SDK will be governed by the Android Software Development Kit License Agreement (available at https://developer.android.com/studio/terms and such URL may be updated or changed by Google from time to time), which will terminate when Google issues a final release version.
Your testing and feedback are important part of the development process and by using the SDK, you acknowledge that (i) implementation of some features are still under development, (ii) you should not rely on the SDK having the full functionality of a stable release; (iii) you agree not to publicly distribute or ship any application using this SDK as this SDK will no longer be supported after the official Android SDK is released; and (iv) you agree that Google may deliver elements of the SDK to your devices via auto-update (OTA or otherwise, in each case as determined by Google).
WITHOUT LIMITING SECTION 10 OF THE ANDROID SOFTWARE DEVELOPMENT KIT LICENSE AGREEMENT, YOU UNDERSTAND THAT A DEVELOPMENT VERSION OF A SDK IS NOT A STABLE RELEASE AND MAY CONTAIN ERRORS, DEFECTS AND SECURITY VULNERABILITIES THAT CAN RESULT IN SIGNIFICANT DAMAGE, INCLUDING THE COMPLETE, IRRECOVERABLE LOSS OF USE OF YOUR COMPUTER SYSTEM OR OTHER DEVICE.
Download Android 15 OTA system image
Before downloading, you must agree to the following terms and conditions.
Terms and Conditions
By clicking to accept, you hereby agree to the following:All use of this development version SDK will be governed by the Android Software Development Kit License Agreement (available at https://developer.android.com/studio/terms and such URL may be updated or changed by Google from time to time), which will terminate when Google issues a final release version.
Your testing and feedback are important part of the development process and by using the SDK, you acknowledge that (i) implementation of some features are still under development, (ii) you should not rely on the SDK having the full functionality of a stable release; (iii) you agree not to publicly distribute or ship any application using this SDK as this SDK will no longer be supported after the official Android SDK is released; and (iv) you agree that Google may deliver elements of the SDK to your devices via auto-update (OTA or otherwise, in each case as determined by Google).
WITHOUT LIMITING SECTION 10 OF THE ANDROID SOFTWARE DEVELOPMENT KIT LICENSE AGREEMENT, YOU UNDERSTAND THAT A DEVELOPMENT VERSION OF A SDK IS NOT A STABLE RELEASE AND MAY CONTAIN ERRORS, DEFECTS AND SECURITY VULNERABILITIES THAT CAN RESULT IN SIGNIFICANT DAMAGE, INCLUDING THE COMPLETE, IRRECOVERABLE LOSS OF USE OF YOUR COMPUTER SYSTEM OR OTHER DEVICE.
Download Android 15 OTA system image
Before downloading, you must agree to the following terms and conditions.
Terms and Conditions
By clicking to accept, you hereby agree to the following:All use of this development version SDK will be governed by the Android Software Development Kit License Agreement (available at https://developer.android.com/studio/terms and such URL may be updated or changed by Google from time to time), which will terminate when Google issues a final release version.
Your testing and feedback are important part of the development process and by using the SDK, you acknowledge that (i) implementation of some features are still under development, (ii) you should not rely on the SDK having the full functionality of a stable release; (iii) you agree not to publicly distribute or ship any application using this SDK as this SDK will no longer be supported after the official Android SDK is released; and (iv) you agree that Google may deliver elements of the SDK to your devices via auto-update (OTA or otherwise, in each case as determined by Google).
WITHOUT LIMITING SECTION 10 OF THE ANDROID SOFTWARE DEVELOPMENT KIT LICENSE AGREEMENT, YOU UNDERSTAND THAT A DEVELOPMENT VERSION OF A SDK IS NOT A STABLE RELEASE AND MAY CONTAIN ERRORS, DEFECTS AND SECURITY VULNERABILITIES THAT CAN RESULT IN SIGNIFICANT DAMAGE, INCLUDING THE COMPLETE, IRRECOVERABLE LOSS OF USE OF YOUR COMPUTER SYSTEM OR OTHER DEVICE.
Download Android 15 OTA system image
Before downloading, you must agree to the following terms and conditions.
Terms and Conditions
By clicking to accept, you hereby agree to the following:All use of this development version SDK will be governed by the Android Software Development Kit License Agreement (available at https://developer.android.com/studio/terms and such URL may be updated or changed by Google from time to time), which will terminate when Google issues a final release version.
Your testing and feedback are important part of the development process and by using the SDK, you acknowledge that (i) implementation of some features are still under development, (ii) you should not rely on the SDK having the full functionality of a stable release; (iii) you agree not to publicly distribute or ship any application using this SDK as this SDK will no longer be supported after the official Android SDK is released; and (iv) you agree that Google may deliver elements of the SDK to your devices via auto-update (OTA or otherwise, in each case as determined by Google).
WITHOUT LIMITING SECTION 10 OF THE ANDROID SOFTWARE DEVELOPMENT KIT LICENSE AGREEMENT, YOU UNDERSTAND THAT A DEVELOPMENT VERSION OF A SDK IS NOT A STABLE RELEASE AND MAY CONTAIN ERRORS, DEFECTS AND SECURITY VULNERABILITIES THAT CAN RESULT IN SIGNIFICANT DAMAGE, INCLUDING THE COMPLETE, IRRECOVERABLE LOSS OF USE OF YOUR COMPUTER SYSTEM OR OTHER DEVICE.
Download Android 15 OTA system image
Before downloading, you must agree to the following terms and conditions.
Terms and Conditions
By clicking to accept, you hereby agree to the following:All use of this development version SDK will be governed by the Android Software Development Kit License Agreement (available at https://developer.android.com/studio/terms and such URL may be updated or changed by Google from time to time), which will terminate when Google issues a final release version.
Your testing and feedback are important part of the development process and by using the SDK, you acknowledge that (i) implementation of some features are still under development, (ii) you should not rely on the SDK having the full functionality of a stable release; (iii) you agree not to publicly distribute or ship any application using this SDK as this SDK will no longer be supported after the official Android SDK is released; and (iv) you agree that Google may deliver elements of the SDK to your devices via auto-update (OTA or otherwise, in each case as determined by Google).
WITHOUT LIMITING SECTION 10 OF THE ANDROID SOFTWARE DEVELOPMENT KIT LICENSE AGREEMENT, YOU UNDERSTAND THAT A DEVELOPMENT VERSION OF A SDK IS NOT A STABLE RELEASE AND MAY CONTAIN ERRORS, DEFECTS AND SECURITY VULNERABILITIES THAT CAN RESULT IN SIGNIFICANT DAMAGE, INCLUDING THE COMPLETE, IRRECOVERABLE LOSS OF USE OF YOUR COMPUTER SYSTEM OR OTHER DEVICE.