Product name: 2.1 channel Bluetooth audio power amplifier module Product model: -MT21 Bluetooth version: 5.0 (within 10 meters) Input sensitivity: 500mV Input : Bluetooth input + AUX input Number of channels: 2.1 channels Adaptive power supply: DC12-24V/5A or more (the higher the voltage, the greater the output power) Adapted speaker: 20-100W|4-8Q Output power: left and right channels Less than 50W Subwoofer Less than 100W Protection mechanism: anti-reverse connection, overheating, overcurrent, short circuit protection Product size: 93mm x 90mm x 22mm Due to different batches, there may be differences in product appearance, color, and printed text, which will not affect the use. Color: Black Material: metal+plastic Package Contents: 1 x Amplifier board 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.