diff --git a/core/java/android/bluetooth/BluetoothHeadset.java b/core/java/android/bluetooth/BluetoothHeadset.java
index 9414a8d..82e76bd 100644
--- a/core/java/android/bluetooth/BluetoothHeadset.java
+++ b/core/java/android/bluetooth/BluetoothHeadset.java
@@ -199,6 +199,18 @@
     public static final String VENDOR_RESULT_CODE_COMMAND_ANDROID = "+ANDROID";
 
     /**
+     * A vendor-specific AT command
+     * @hide
+     */
+    public static final String VENDOR_SPECIFIC_HEADSET_EVENT_XEVENT = "+XEVENT";
+
+    /**
+     * Battery level indicator associated with {@link #VENDOR_SPECIFIC_HEADSET_EVENT_XEVENT}
+     * @hide
+     */
+    public static final String VENDOR_SPECIFIC_HEADSET_EVENT_XEVENT_BATTERY_LEVEL = "BATTERY";
+
+    /**
      * Headset state when SCO audio is not connected.
      * This state can be one of
      * {@link #EXTRA_STATE} or {@link #EXTRA_PREVIOUS_STATE} of