DuaFire Wireless Portable Bluetooth Stereo Music Receiver for 3.5mm Audio Devices SpecificationBluetooth Version 2.1 (Class II)Range: 33 ftWork Time: Up to 7 Hours ConnectionPair to the Bluetooth Stereo headset automatically. RangeBluetooth receiver is compatible with the entire home stereo with 3.5mm interface Dimension60 x 24 x 9 mmWeight: 10 g ApplicationSmall, lightweight and durable