Fits two-way radios (audio only), and other two way radio accessories with 3.5mm earphone jack Fits two-way radios (audio only), radio speaker mics, remote mics, MP3 players, and other audio accessories with 3.5mm earphone jack. Output level: 72dB, Rated input power: 0.1W, Maximum input power: 0.2W, Output impedance: 32 ohms. Polyurethane jacketed, Heavy Duty Material, Superb Audio Quality, Rugged Design. Reinforced earphone clip provides cable retention and eliminates strain on earphone.