The ITC-402P intercom is an easy to install 2-place, panel- mount intercom designed for quiet, continuous cockpit communications. Unlike intercoms using squelch circuitry, the ITC-402P uses state-of-the-art noise reduction technology to monitor & eliminate up to 110db of mic background noise. The unit has one volume control, a Pilot/All switch, & PTT keying. Other features include a music input with ATC auto-muting and a second un-muted auxiliary input for warning devices. 12/24V. Size: 2.1″x 1.1″x 3.2″ Wt: 4 oz. 3 yr mfg warranty.