Rabbit Listen Only Classic Ear Hook is made of soft flexible rubber. In addition to comfort, the ""outer"" earpiece feature allows the unit to be worn by multiple users without compromising hygiene. The comfortable speaker rests securely in your ear, producing a rich, full, natural sound that can be heard only by the user wearing the earpiece. The speaker rotates to affix to either ear and moves up and down for a custom fit. Available for 2.5mm, 3.5mm, 3.5mm threaded audio jacks. FEATURES & BENEFITS Privately listen to your radio and still hear your surrounding environment Traditional earhook-style listen only earpiece swivels to left or right ear Comfortable style promotes hygiene with earhook resting on the ear, not inside