Dual deck recording system for single line or two-line telephones. Features • Offers the most recording time available on a standard cassette based system - 10 full hours • Unattended recording, 20 hours total recording on two d-140 standard cassettes. • Automatic transfer of recording function from deck 1 to deck 2 when tape ends (single line phone). • Simultaneously records both lines on 2-line phone system (5 hours unattended per line). • Quality expertly modified panasonic cassette recorders. • DC operation- (4) AA batteries. • Simple modular connection to phone system- duplex plug included. • Auto shut off at end of tape saves battery power (system operates with case open or closed). The Tele-Twin 20 recorders may also be removed from the case for playback of recordings or to be used as 2 independent single-line telephone recorders. The Tele-Twin 20 is the solution to extra long play telephone recording. Package includes 10 foot modular telephone connector cable for single-line or two-line jacks, four AA batteries, two D-140 high-grade recording cassettes duplex jack, and recorders It is the user's responsibility to ensure equipment is used in accordance with the law of the jurisdiction where the equipment is utilized. "