Specifications: Bluetooth Version 2.1 No software installation required; plug-and-play operation Supports A2DP and AVRCP profiles Compatible with Bluetooth stereo headsets and earphones for play/pause, forward/backward controls Automatic pairing (no manual button press required) Default pairing PIN codes: 1234, 0000, 8888 Operating frequency range: 2.42–2.480 GHz Automatic standby mode activates when no compatible headset/earphone is detected, conserving power Compatible with iPhone, iPod mini, iPod nano, iPod video, and other devices with 30-pin dock connector Type: Bluetooth transmitter Material: ABS Operating current: 40 mA (maximum) Effective range: 10 meters Dimensions: 9 cm x 6 cm x 1 cm (approximately 3.54" x 2.36" x 0.39") Note: Color may vary slightly due to lighting and screen settings. Slight dimensional variations may occur due to manual measurement. Package Includes: 1 x Bluetooth transmitter