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This microphone enables the wearer of a standard German gas mask to use a "loud speaker" system without removing the gas mask.

There are no markings of any identification value on either the microphone or the con-tainer.

The container (A) consists of a black plastic cup with a screw cap of similar material. The overall dimensions of the cup are: height, 5.9 inches; diameter, 2.8 inches. The ex-ternal thread of the microphone (B) fits the nozzle of the standard German facepiece and the two wire prongs keep the inlet valve in the latter open. The bottom of the micro-phone proper is internally threaded to fit the standard German canister and just above the thread is a thin rubber semicircular valve which supplants the valve which is kept open in the nozzle of the facepiece.

The internally threaded over (C) is 2.5 inches in diameter and is attached to the mi-crophone by a wire, 14.8 inches long and fitted with double prong plugs at each end.

Three projecting ribs on the inside of the container support the microphone proper so that it does not rest on the bottom while the container cover secures the microphone in a fixed position.

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