Bluetooth V2.1 technology. Need not setup any software and very easy to use. Support profile: A2DP & ARVCP. Support paired bluetooth-compatible stereo headsets/earphones to control play/pause,forward/backward. Support automatism paired (no button). Support paired pin code: 1234, 0000, 8888. Range of frequency: 2.42 to 2.480 GHz(SIM) spectrum. Support automatism standby mode: standby mode is started to save power when the stereo bluetooth-compatible headsets/earphones is not found in due time. Support for iPhone, for iPod mini, for iPod nano, for iPod video, etc. Compatible with 30-pin dock. Type: bluetooth-compatible Transmitter Material: ABS Range of Frequency: 2.42 to 2.480GHz( SIM) Spectrum Working Current: 40mA(Max) Distance: 10 Meters Size: 9cm x 6cm x 1cm/3.54" x 2.36" x 0.39" (Approx.) Notes: Due to the light and screen setting difference, the item's color may be slightly different from the pictures. Please allow slight dimension difference due to different manual measurement. Package Includes: 1 x bluetooth-compatible Transmitter