Telex acc4000XL Cassette Duplicator Have Master unit and several Slave units | eBay
Telex Copyette 1 To 3 Cassette Duplicator-Mono | PSSL ProSound and Stage Lighting
Picked up a Telex CD4 Duplicator for free on FB because it was "broken" and didn't power on. Turns out you need to put a cassette in the master slot for the