The razor walkie-talkie attachment features a voice activated transmit (vox) which allows for hands-free communication up to 2-3 miles.It has 22 channels and 99 sub-channels for your family and friends to join.It is custom designed to fit onto the razor muff.(does not work with razor quad muffs)Type: AttachmentFunction: Ability to CommunicateBattery: AAAProofs: AAA (2) IncludedColor: BlackCompatible With: Walker's Razor Muffs