Physical description

Heavy cast Aluminium box with hinged lid. Colour is drab olive. Each end has a belt loop. There is a semi rotating clip on the front of the lid section to hold it shut. Inside are Morse Key, 3 switches, Buzzer Assembly, 3 terminals and a built in battery box.
Inside the lid are the circuits for the device and operating instructions. On lid is stamped 'D^D'. On front is "Wireless Remote Control Unit A, Serial No. 18017. Inside is marked serial 18017.

Inscriptions & markings

Inside on Battery cover is: - “Wireless Remote Control Units 'A'./ Stromberg Carlson Serial No....... 1941”
Inside on front panel is :- “Serial No. 18017/ D^D Vac No. ZA 7533".