Stores reference 10A/11994. Black painted alloy microphone, often referred to as the '1941' pattern although it was actually introduced in October 1940. Also known as the 'type 21', but this is the reference allocated to it when fitted to a wiring loom. Overall shape is good and while it retains the majority of the original paint there is loss on exposed edges. The on/off switch is very stiff. With Air Ministry and King's crown markings. Remnants of the loom remain. The type 20 microphone was mainly used in conjunction with the type D cloth oxygen mask. A reasonable example. Stock code O4598A.