Stores reference 10A/11994. Black painted alloy microphone, often referred to as the '1941' pattern although actually introduced in October 1940. Also known as the 'type 21' but this is the reference given to it when fitted to a wiring loom. This example is in excellent condition with only very minor paint loss. Air Ministry and King's crown markings. These microphones were used in conjunction with the type D cloth oxygen masks. Stock code H22142A.