BT 21A Electret Transmitter Microphone (Used)


A genuine replacement BT 21A ‘all red’ transmitter (microphone); these are used but have been cleaned and fully tested.  We are unable to source brand new units and so these refurbished transmitters are the best option as a replacement for old, worn or malfunctioning carbon granular transmitters, designed for use with all GPO & BT 700 series telephones (except trimphones).

28 in stock

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