Features:OOTDTYStereo, a highquality dual power amplifier board for musicIt supports both AUXinput and Bluetoothconnection (BT5.0) for highernsmiion efficiency and longer distancesThe integrated highPerformance proceor chip is a ClaD amplifier integrated circuit. The modulation frequency can reach 1.2 MHz, and the distortion of highpower output is le than 0.1%. Built in LCfilter , ing the humanvoice clearer.Both AUXand Bluetoothcompatible inputs are supported, supporting Bluetoothcompatible version 5.0.The nsmiion distance is longer, reaching up to 49 feet in outdoor environments. If your device does not have a Bluetoothcompatible modules, you can also input audiosignals through .5mm headphoneplug.Protections mechanism: The amplification board has overheating protections, overvoltage protections, undervoltage protections, and short-circuit protectionsSpecifications:Item: ZK-TB21 Power Amplifier BoardChip:TPA3116D2Input : DC12V-24V5APower output: 50Wx2 (left and right s)+100W (subwoofer): 2.1 stereooutputOutput impedance: 4-8ΩBluetoothCompatible version: BT5.0Length:approx 118mm/4.65inPackage Includes:1Set ZK-TB21 Power Amplifier BoardNote:Due to the probl of lighting effects and angles, there will be certain tolerances in the product, please understand.Please allow 0-1cm error due to the manual measurment.