Removing your protective earmuff in a loud work environment to talk on your phone can be hazardous to your hearing. It's also difficult to hear the call, and often interrupts your work. The Sync Wireless Earmuff with Bluetooth 4.1 keeps your ears protected, your communication clear, and your hands free. It also allows you to stream music wirelessly, thus eliminating cumbersome and potentially dangerous cords. Patented Air Flow Control Technology delivers an NRR of 25, and proprietary Volume Control Technology limits audio device output to a safe 82 db. The rechargeable battery lasts 16 hours or more when fully charged, and the earcups and headband are cushioned for long-wearing comfort. Features Bluetooth 4.1 connectivity Hands-free operation Music streaming Volume Management Technology Air Flow Control Technology Adjustable boom mic Padded headband earcups 16 hour rechargeable battery USB charger with wall adapter Includes Earmuff USB charger with wall adapter 3.5 mm Aux Cable User Manual Specifications Color Black with Red Accents NRR 25 SOLD QUANTITY 1