Stores reference 10A/12572. Distinctive black painted 'ball-shaped' microphone casing with angular metal on/off switch mounted on the top. Complete with remnants of the original wiring loom and rubber grommet at the point where the loom enters the casing. It retains approximately 40% of the original paint although this is rather dulled. The switch is currently siezed but may free up with lubrication/care. The loom securing tab is still in place - see photographs. The type 27 (more commonly known as the Type 28 when 'mounted' on a wiring loom) was sometimes used with the E-series, type G oxygen masks and the second pattern microphone carrier masks. A reasonable used example. Stock code O19641.