Features: brand new and high quality SPDIF + AUX Port: You get maximum flexibility with support for both 3.5mm (AUX and RCA) and optical (SPDIF) digital, both input and output are supported. In transmit mode, this device can pair with two Bluetooth-enabled headphones or speakers to for play music simultaneously. In receive mode, it can pair with two for smart phones at the same for time, but the music played only by one mobile phone. If you want to switch to another phone to for play music, you need to pause or end the music on the current phone. Using CSR BC8670 Bluetooth-compatible chip as the core data processing, the Bluetooth-compatible version is: 5.0 Transmitting power: Class II, use range within 10 meters (the actual range depends on the device connected to it) The main chip data storage uses internal 16M FLASH memory; Frequency range: Bluetooth-compatible standard, 2.4022.480GHz; Support A2DP AVRCP protocol; Support SBC, APT-X and other Codec Specifications: Chipset: CSR BC8670 Supported Protocol: A2DP AVRCP Supported CODEC: APT-X, SBC and others Bluetooth-compatible Version: V5.0 Frequency: 2.40GHz-2.480GHz Transmit Power: Class II, within 10 meters Charging Input: for DC 5V,300MA Working for Time (AUX, reception status): 15H Working for Time (AUX, for launch status): 15H Working Time: (SPDIF, reception status): 12H Working Time: (SPDIF, for launch status): 12H Battery: 350mAh Rechargeable Li-polymer Battery Package Weight: 127g Dimension: 60 x 60 x 18.4mm / 2.36 x 2.36 x0.72inch The supported Bluetooth-compatible speaker or headset pairing security keys are: 0000, 1111, 8888. Charging time:2 hours; Charging input requirements: 5V for DC 300MA 350mAh lithium ion polymer rechargeable battery Working temperature: -1055 Note: Due to the problems of lighting effects and shooting angles, there will be certain tolerances in the product, please understand. Please allow 0-1cm error due to the manual measurment. Package includes: 1 x Bluetooth-compatible 4.1 Transmitter and Receiver 1 x USB Cable 1 x 3.5mm AUX Cable 1 x Optical Cable 1 x RCA Cable 1 x User Manual