Active noise canceling .
Wired or wireless headsets.
Up to 20 meter indoor wireless range.
High quality big size comfortable earmuffs.
Lightweight headphone with adjustable headband .
Rechargeable 350 mAh battery at 12 hours working time.
CSR 8635 Compatible with all audio equipment with Bluetooth .
Φ40 mm speaker at crystal clear and powerful sound with good sound isolation.