diff --git a/protobuf_definitions/message_formats.proto b/protobuf_definitions/message_formats.proto
index 30db8dba..17aac8be 100644
--- a/protobuf_definitions/message_formats.proto
+++ b/protobuf_definitions/message_formats.proto
@@ -940,6 +940,7 @@ enum GuestPortDeviceID {
   GUEST_PORT_DEVICE_ID_BLUEPRINT_SUBSEA_OCULUS_M370S = 42; // Blueprint Subsea Oculus M370s.
   GUEST_PORT_DEVICE_ID_WATERLINKED_SONAR_3D15 = 43; // Waterlinked Sonar 3D-15.
   GUEST_PORT_DEVICE_ID_CERULEAN_TRACKER_650 = 44; // Cerulean Tracker 650.
+  GUEST_PORT_DEVICE_ID_BLUEYE_EXTERNAL_USB_STORAGE = 45; // Blueye External USB Storage
 }
 
 // Guest port number.