Shop name:Chong Qing Shuo Yue Ke Ji You Xian Gong Si QCC3031/QCC3034 support , AAC, , APTXLL, APTXHD AUX audio input, low power consumption, power on, the default volume is maximum, 2x4/8 ohm 10W/15W, external IPEX generation antenna 8-22V power supply (at 16V3A, the maximum output power is 2x15W) VCC, GND: power supply pins, with reverse connection protection Power amplifier board size: 7.1x4.3CM Fixing hole distance: 6.6x3.8CM Key Description: "VOL+": Short press to increase the volume, long press to increase the volume "VOL-": Short press to decrease the volume, long press to decrease the volume continuously "NEXT": short press a song "PREV": Short press the previous song "PLAY": Short press to play/pause Special function description: "PLY": Long press for 3 seconds to force enter pairing mode, long press for 6 seconds to clear the pairing list colour:Green Material:plastic Package Contents: 1 x Amplifier Board Only the above package content, other products are not included. Note: Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.