Pyramex Amp BT Electronic Earmuff 26dB Tan with Bluetooth FF28A424 PI. NRR 26dB Bluetooth compatible. Noise suppression after 85db. Automatic shut-off after four hours. 3.5 mm AUX jack for use of MP3 and mobile devices. Quad microphones. 2 AAA batteries included. Features of Pyramex Amp BT Electronic Earmuff 26dB Tan with Bluetooth: Nrr 26db Bluetooth compatible Noise suppression after 85db Automatic shut-off after four hours 3.5 mm aux jack for use of mp3 and mobile devices Quad microphones Package Contents: Pyramex Amp BT Electronic Earmuff 26dB Tan with Bluetooth Venture Gear Electronic Earmuff. NRR 26dB Bluetooth compatible. Noise suppression after 85db. Automatic shut-off after four hours. 3.5 mm AUX jack for use of MP3 and mobile devices. Quad microphones. 2 AAA batteries included. PIVGPME31BT