The TA-341/TT is a four-wire, transistor, local-battery telephone intended for use in sheltered areas. It is designed for use with tactical automatic switches but also can be used in a point-to-point mode. Up to four sets can be bridged across a single four-wire line for extension service. DTMF tones activated by a push-button key sender are used for signaling. Range is 2 miles. Uses for C-Cell batteries. Usable in conventional point-to-point telephone line (plug my need changed. Signal out of 900-3400 Hz with DTMF digital tone, 90 V 20 Hz ringing signal in. Comes with a heavy duty canvas carrying case with zipper and handle. Used but great condition. Complete. Measures approx 4.5 in. x 10.5 in. x 10.5 in.