Xfox&reg; M1PE0901 Listen only Earpiece RHF 617-1N 3.5mm Surveillance Plug Receiver Audio Earpiece with Clear Acoustic Coil Tube Earbud For Two-Way Radios Transceivers and Radio Speaker Mics Xfox Original Listen only RHF 617-1N 3.5mm Surveillance Plug Audio Earpiece. 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. Reinforced earphone clip provides cable retention and eliminates strain on earphone. Heavy Duty Material. Super Audio Quality. Rugged Design. Ideal for high noise level environments and discrete listening.