Description: With high quality, onboard 2W single channel power amplifier.The 3.5mm gold-plated headphone jack connecet headphones or external speakers. With MicroUSB power supply interface, with mobile phone data cable, using mobile power or USB charger power supply, can also be used 3.7V lithium battery, USB 5V power supply. Convenient to wire and refit; 4 buttons on the board for setting operation. Support MP3 format, playing power on automatically, LED indocator light when module is working. Mp3 lossless decoders power amplifier Mp3 player module Mp3 decoder board support TF card and USB. Support TF Card (mobile phone memory card), U disk playback mode With the speaker terminals without welding. Specification: The "Prev/V--" key : " short press "is switching to"the last song ,"long press" is for "volume decreasing" The "Next++" key : " short press "is switching to"the next song","long press"is for"volume increasing " The "P/P/Mode" key :"short press"is switching to "play / pause", " long press"is U disk and TF Card mode's selection The "Repeat" key :"short press" is switching cyclically "single / song" (no press function) Power range: 3.7-5.5V Dimension: 45mm*36mm Package Includes: 1 Piece Mp3 Lossless Decoders Decoding Power Amplifier (6 Pack) Note: 1 "long press" time is about 2S. 2 If you use U disk mode, some suggestions of 5V power supply, some U disk doesn’t support 3.7V power supply.