Amplifier board size: 6.2x4.4CM Bluetooth power amplifier board (dual 4O3W), support serial port AT to change bluetooth name, support serial port AT control, Bluetooth (with call), transmit audio input, key switch, neutral tone, etc. It can be used as a Demo test board for BK3266 transmitter module. Facilitate customer development and testing Neutral tone = beep tone or electronic tone Power on, the default transmission function, you can switch between transmission and by pressing the button Color: green Material: PCB Launch Instructions: 1. that the slave is in the pairing state (requires the slave to have no pairing password) 2. After the transmitter module is powered on, press and hold the "PLY button" for 6 seconds until the indicator light flashes to searching for the slave 3. After the pairing is successful, the indicator light of the transmitter module is always on 4. After each power-on, the connection is normal, first power on the transmitter, and then power on the slave (requires the slave to have the power-on return function) Package Contents: 1 x Amplifier Board Only the above package content, other are not included. Note: Light reflection and different displays may cause the color of the item in the a little different from the real thing. The measurement allowed error is +/- 1-3cm.