Circumaural design supports enclosed sound. Digital audio clarity and transmission range up to 238ft. Switch between dynamic bass and virtual surround sound modes. Supports analog and digital audio inputs. Multi-purpose transmitter - charging cradle and docking station. Multi-receiver transmission supports two pairs of headphones. Up to 18 hours of battery life. 3.5mm Audio input. Optical digital audio input. Includes: TR 175 Transmitter. Optical cable. Audio cable. Power supply with 4 adapters (EU UK US & AUS). 2 AAA Rechargeable batteries.