Spy Centre carries all types of security equipment including the telephone recorder, the wireless camera, video detection equipment and custom digital surveillance systems. The Standard Atr telephone recorder automatically starts and stops when the phone is in use. With a 120 minute tape you can record for 1 hour per side. This unit can operate with battery or AC power. Want something more? For the longest audio record time available on a standard cassette format, the Tele-Twin 20 telephone voice recorder doubles the competition. Dual cassette decks give you a total 10 hour quality recording. There is no battery drain between conversations so elapsed time between recordings is no problem.