diff --git a/en/source/add-device.html b/en/source/add-device.html
index 783fd6f..d9f42f8 100644
--- a/en/source/add-device.html
+++ b/en/source/add-device.html
@@ -417,5 +417,48 @@
   </tbody>
 </table>
 
+<h3 id="ANDROID_VENDOR_KEYS">Set ANDROID_VENDOR_KEYS to connect over USB</h3>
+
+<p>The <code>ANDROID_VENDOR_KEYS</code> environment variable enables device
+manufacturers to access production builds over <code>adb</code>. Generate a key
+for each release that every device will accept, store those internally (such as at
+<code>vendor/oem-name/security/adb/</code>), and then use
+<code>ANDROID_VENDOR_KEYS</code> to tell <code>adb</code> to use these canonical
+keys rather than random keys.</p>
+
+<p>Use the <code>ANDROID_VENDOR_KEYS</code> environment variable to
+point to the directory containing the generated <code>adb</code> public and
+private keys used for encryption. The private key is stored in file. The public
+key is stored in file.pub. The <code>ANDROID_VENDOR_KEYS</code> environment
+variable points to a file or directory where the generated key pairs are
+stored.</p>
+
+<p>This variable is set to a file or directory that contains 2048-bit RSA
+authentication key pairs generated with the <code>adb keygen</code> file command.
+These key pairs are in addition to the RSA key pairs generated by the ADB
+server. An RSA key pair is needed when you use <code>adb</code> to connect over
+USB for the first time.</p>
+
+<p>You must accept the host computer's RSA key to explicitly grant
+<code>adb</code> access to the device. By default key pairs generated by the
+ADB server are stored in the following key store directories as
+<code>adbkey</code> (private key) and <code>adbkey.pub</code> (public key):</p>
+
+<p>For file locations, on MacOS, this will likely be:
+<code>$HOME/.android</code>.  On Windows and Linux, this will be:
+<code>%USERPOFILE%\.android</code>. On Windows, RSA authentication keys can
+also be in <code>C:\Windows\System32\config\systemprofile\.android</code> in
+some cases. When the ADB server needs a key, it first searches the ADB server
+key store directory. If no keys are found, it then checks the
+<code>ANDROID_VENDOR_KEYS</code> environment variable. If no keys are found,
+the local ADB server generates and saves a new key pair in the ADB server key
+store directory.</p>
+
+<p class="note"><strong>Note:</strong> You can override the default directory
+where the ADB server stores RSA keys by setting the
+<code>ANDROID_SDK_HOME</code> environment variable. On the device, keys are
+stored in the <code>/data/misc/adb/adb_keys/</code> file, and new authorized
+keys are appended to the same file as you accept them.</p>
+
   </body>
 </html>