It is safe to use this amplifier board because it has protection mechanism including electrostatic protection, overcurrent protection, short circuit protection, overheating protection.This amplifier board uses Bluetooth-compatible 5.1 chip and 2.1 stereo sound channel, which can bring you HiFi and HD-compatible sound quality.It is constructed of PCB material. It supports right and left channel, high and low tones independent adjustment and mobile phone APP control, which is easy to use.The length of this product is 14.1cm and width is 13.1cm. The thickness is 2.7cm.This amplifier board is suitable for development and debugging.Item Name: Amplifier BoardMaterial: PCBModel: YS-AS21Bluetooth-compatible Version: 5.1Input Method: Bluetooth-compatible+AUX+U Disk+USB Sound CardVolume Adjustment: Encoder Knob AdjustmentPower Supply: DC18-38VVoltage Gain: 30dBOutput power: Left and Right Channels: