Wireless Hearing protector (earmuff) connects to bluetooth enabled devices for streaming music and communication SYNC Wireless earmuffs offer a significant level of hearing protection and uncompromised stereo sound by easily plugging into any portable music device; MP3 or smartphone, but performs as a traditional passive earmuff when an audio device is not plugged in. You can stay protected by controlling music and placing/ending calls without removing mobile device from your pocket.