Retevis 1 Pin Throat Mic 3.5mm Covert Acoustic Tube Earpiece Headset with Finger PTT Slow Rebound Earbud for Cellphone (1 Pack) 1 pin throat Mic Microphone acoustic tube covert earpiece headset with finger PTT for cellphone; Compatible with any device that 3.5mm jack is included; such as computer cell phone Provides private communicates; and transmit the sound by vibration not by the mic; great use in noise environment; Such as military; paintball; riding; security;police;bouncer; warehouse Flexible enough to adjust the size depends on your neck; and it fit well on neck to transmit crystal sound to your partners Clear surveillance style tube wraps behind the ear with earpiece fitting securely inside the ear; Reversible earpiece works in either ear; press the button lightly in the line to stop talking Simple and convenient return process; 60 days warranty provide by us and 30 days no reason to return