Tenq 3.5mm Plug Surveillance Receiver Listen Only Audio Earpiece for 2 Way Radio Transceivers and Radio Speaker Mics works with standard, Incom, Yaesu, Alinco, Motorola and Adi transceivers and also fits radio speaker mics, MP3 players and similar devices with 3.5mm connector Listen Only Audio Earpiece for 2-way RadioEarpiece: Clear, hypo-allergenic acoustic tube gives a discreet look and provides perfect sound clarity Durability: Flexible and durable high grade Kevlar cable for demanding applications Speaker diameter: 15mm, Output level: 72dB, Rated input power: 0.1W, Maximum input power: 0.2W, Output impedance: 32 ohms. Uses: Excellent for use in police, military, nightclubs, bars, paintball, security, restaurants, hotels, bouncer, warehouses, and noisy environments