GPO, TELEPHONE RECEIVER INSET, INSERT, 3/3T, FOR 700 TELEPHONE & TRIMPHONE
GPO, TELEPHONE RECEIVER INSET, INSERT, 3/3T, FOR 700 TELEPHONE & TRIMPHONE
Used in many 700 type telephones. 20 ohms resistance.
Later Receiver Insert No. 4's comprised of a No. 3T inserted into a plastic housing which resembled the No.4 - dimension wise.