LETV LEME EB30A Wireless Bluetooth 4.1 Stereo Headphones with Microphone Noise Cancelling Headphones Comportable Earmuffs Earphones On-ear Headsets (blue) Implemented with Bluetooth 4.1 technology allows less power consumption while more reliable connection, backward compatible with all Bluetooth- enabled devices (Bluetooth V2.1 and over) Excellent acoustic experience with 40mm moving coil drivers featuring triple frequency equilibrium for a particularly strong bass performance Built-in high sensitivity microphone features ultra-clear sound quality with noise reduction & echo cancellation technology Build-in rechargeable battery supports up to 10 hours continuous playtime & up to26 days standby time Provide a longer transmission distance of up to 30 feet improve the maximum stability