Fangrui Product Details Board Size: 7.9x4.5cm, Fixing Hole Distance: 7.4x4cm Qcc5125 Supports /aac//aptxll/aptxhd/ad/ldac Aux Audio Input, Low Power Consumption, Power On, Maximum Default Volume, 2x4/8 Ohms 10w/15w, Supports External First Generation Antenna, Knob Switch And Volume 7-15v Power Supply (at 12v3a, The Maximum Output Power Is 2x15w) Vcc, Gnd: Power Supply Pin, With Reverse Connection Protection Key Description: Kcom: Key Common Terminal Vol+: Short To Increase The Volume, Long To Continue The Volume Increase. Vol-: Short To Decrease The Volume, Long To Continue The Volume Decrease. Next: Short Song Prev: Short The Previous Song Play: Short To Play/pause Special Function Description: Ply: And Hold For 3 Seconds To Force Into Pairing Mode, And Hold For 6 Seconds To Clear The Pairing List Specifications:b:qcc5125 Ldac Colour:green Material:pc Package Contents: 1 * Amplifier Board(the Circuit Board Printing Is Slightly Different, Which Does Not Affect The Use) Only The Above Package Content, Other Products Are Not I