diff --git a/radio/1.6/IRadio.hal b/radio/1.6/IRadio.hal
index eb20542..747b2f2 100644
--- a/radio/1.6/IRadio.hal
+++ b/radio/1.6/IRadio.hal
@@ -21,6 +21,7 @@
 import @1.0::GsmSmsMessage;
 import @1.1::CardPowerState;
 import @1.2::DataRequestReason;
+import @1.4::RadioAccessFamily;
 import @1.5::IRadio;
 import @1.5::AccessNetwork;
 import @1.5::DataProfileInfo;
@@ -305,4 +306,18 @@
      * Response function is IRadioResponse.cancelHandoverResponse()
      */
     oneway cancelHandover(int32_t serial, int32_t callId);
+
+    /**
+     * Requests to set the network type for searching and registering.
+     *
+     * Instruct the radio to *only* accept the types of network provided. This
+     * is stronger than setPreferredNetworkType which is a suggestion.
+     *
+     * @param serial Serial number of request.
+     * @param networkTypeBitmap a 32-bit bearer bitmap of RadioAccessFamily
+     *
+     * Response callbask is IRadioResponse.setNetworkTypeBitmapResponse()
+     */
+    oneway setAllowedNetworkTypeBitmap(
+            uint32_t serial, bitfield<RadioAccessFamily> networkTypeBitmap);
 };