Codified NSN Z4/6625-99-778-6212, in a black finish and manufactured by Sonic Communications so I suspect used primarily to test Clansman audio items used with security service and paramilitary equipment.
Small (120x110x35) unit with 7-pin connector for Equipment Under Test), earpiece socket, antenna socket, and LEDs for test indication. Internally powered by PP3 battery. Good, possibly slightly used, condition. ?25, could post at cost)
Bob
