W800bt plus bluetooth stereo headphones newly upgraded qualcomm® chipset with bluetooth v5.1 qualcomm® aptx™ audio Φ40mm ndfeb driver delivers punchy bass built-in microphone qualcomm® cvc™ 8.0 noise cancellation support connecting between two bluetooth devices simultaneously. the earmuffs are designed with a 15-degree inclination; the head beam can be stretched to a large range, and the earmuffs are made of soft leather which all provide a comfortable wearing experience. qualcomm® aptx™ audio decoding format, which supports both 16bit and 24bit audio signals with a sampling rate of up to 48khz. this provides a natural sound, rich in details and quality. qualcomm cvc8.0 accurately picks up voices and eliminates background and environmental noise, leading to clearer communication during calls.40mm ndfeb magnetic moving coil units provide a large sound field with powerful bass and enriched voice notes, producing a dynamic sound. the built-in lithium battery has a large capacity which can provide up to 55 hours of wireless listening time. edifier connect provides a more intelligent and personalized listening experience. it can expand the functions of your headphones so you can select a different sound mode, customize the headphone pairing name, etc. pairing two devices, easily switch over- support connecting with two bluetooth devices simultaneously. easily switch between work and entertainment. edifier has a long history in the audio industry. each product is subjected to a set of reliability test criteria, and many test requirements are higher than national standards to guarantee quality.