1. Current Input Reverse Protection, Short Circuit Protection, Overcurrent Protection, Overtemperature Protection 2. High Efficiency 3. , Plus Filter, 20hz Waveform 4. Class D 2.0 Channel Bluetooth Power Amplifier 5. Bluetooth And Auxiliary Input: Users Can Directly Connect Wireless Bluetooth Product Category: High-Efficiency D Class 2.0 Channel Bluetooth Power Amplifier Power Amplifier Chip: Tdpa3116 Working Voltage: Dc9-24v Output Power: Maximum Power 2x50w Stereo (24v/4 Ohms), Can Be Connected To 4/8/16 Ohm Speakers Performance Indicators: Efficiency: 92%, Total Harmonic Distortion Plus Noise: Less than 0.2%, Gain: 32db, Low Quiescent Current, Noise Suppression Protection Function: Power Input Reverse Protection, Short Circuit Protection, Overcurrent Protection, Overtemperature Protection, Undervoltage/Overvoltage Protection Input Mode: 5.0 Bluetooth Audio, 3.5mm Audio Input, 3p_2.54mm Terminal Audio Input Indicator Status: 1. Slow Flash: Aux Connection (3.5mm Audio, 3p2.54mm Audio, 2. Always: Bluetooth Connection, 3 Fast Flash: Playing Music Additional Interface: 2p_2.54mm Cooling Fan (Voltage Range Is Consistent With Working Voltage) It's DIY kits, needs to finish by yourself. Color: As Shown Material: Electronic Component Package Contents: 1 * Audio Amplifier Module Only the above package content, other products are not included. Note: Light reflection 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.