Digital infrared transmission for high quality transfer. Supports Dolby Digital, Dolby Pro Logic II, DTS and MPEG-2AAC formats. High-accuracy, 24-bit surround decoder. 3rd generation Logic 3D processor. Full open air dynamic type headphones. Gyrotrak Head-Tracking System allows direction of sound to remain unchanged even if user moves. 50mm driver units. 12Hz-24khz. Includes: transmitter, AC adapter, NiMH rechargeable batteries, battery charger and optical correction cable.