ANC Active Noise-canceling technology, 2pcs high sensitive microphones, up to -25dB. Built-in CSR8635 Bluetooth chip, CD level lossless Bluetooth transmission. Memory foam and protein leather earmuff, very comfortable for wearing. Proprietary 40mm Large-aperture Drivers. Deep, accurate bass response. Built-in 600mAh rechargeable Li-polymer battery, up to 30h playtime. High-quality Built-in Microphone and NFC Technology.