Specifications:Using bluetooth-compatible 5.0 master chip, JL6925A, a true stereo 5.0 chip, this product has good sound quality and stereo output.It supports auto-return function and WAV, APE, FLAC, MP3 lossless decoding.It uses universal Micro USB 5V power supply, 3.7-5V power supply soldering pad for external 3.7-5V lithium battery power supply modification.With standard 3.5mm stereo audio interface, it would output stereo sound source, it can also inserted into headphones, connected amplifiers and other equipment.With LED indicator, the blue light would on when bluetooth-compatible mode is on.Item Name: bluetooth-compatible Audio ReceiverMaterial: ChipVoltage: 3.7-5VSNR: 90dBTHD+N: -70dBCrosstalk: -86dBDNR: 91dBSupport Profile: A2DP/AVCTP/AVDTP/AVRCP/HFPLOS: >15mFeatures: Stereo Music, DIY, Easy to Use, Lossless DecodingSize: 3cm x 3cm x 0.5cm/1.18" x 1.18" x 0.2" (Approx.)Notes:Due to the light and screen setting difference, the item& 39;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 Audio Receiver