This is a head-mounted stereo headset designed with Bluetooth technology, which can be used as a wired headset and a wireless Bluetooth headset at the same time Applicable to Bluetooth devices such as mobile phones, computers, tablets, etc. Nearly perfect appearance, acoustics, ergonomic design, make you more comfortable, beautiful, and more convenient to use Adjustable folding earphone design to higher wearing comfort and listening effect Advanced digital audio processing and transmission technology, coupled with high-quality speakers, effectively restore stereo music Wireless Type:bluetooth Bluetooth version:V4.1 Frequency range:2.402GHZ-2.480GHZ ISM Band Wireless transmission standard:CLASS 2 Signal distance:10 meters Frequency response:20HZ-20KHZ Signal to noise ratio:80db Speaker output power:2x10mW Status indication:LED indication Battery:Rechargeable polymer battery 3.7V 130mA Charging time:1.5 hours Talk time:10 hours Playing time:10 hours Standby time:250 hours Style:Headphone Volume Control:Yes Is wireless:Yes Model Number:NX-8252 Earcups Type:Semi-open Bluetooth Version:4.1 Features:With Microphone Colour:Black-Red Material:Plastic Package Contents: 1 * Wireless Bluetooth Headphone 1 * USB Cable 1 * 3.5mm Audio Cable 1 * English instruction manual Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.