E-Max Pro Series 30 dB BT ODG Electronic Earmuffs by Caldwell. The E-Max BT Links combine Caldwell's unmatched hearing protection with Bluetooth communication ability via ambidextrous boom microphone. Communicate with multiple users on the range listen to music and protect your hearing all at once with the Links. The Links are compatible with all Bluetooth hearing protection including E-MAX PRO BT Links Power Cords E-MAX PRO BTs and E-MAX Shadows.Features:Connects via bluetoothAllows communication between multiple usersAmbidextrous boom microphoneWorks with other bluetooth hearing protection via comm link