Item Type: Mini Amplifier BoardMaterial: PCBPower Connector: Micro 5p (Reserved for 2.5mm/0.10in Solder Port)Input Voltage: 3.7V-5VAmplifier Operating Mode: Switchable Class AB and Class DANR: 90DBTHD and N: -70DBCrosstalk: -86dbDNR: 91dbOutput Interface:Speaker output port x 2 groups (left and right channel each group), recommended to connect 4 5W-50W power speakers to useUsers can freely switch CLASS AB or CLASS D working mode according to sound preference and power matching.Product Features:Power switch and volume knob integration, the sound is adjusted to the smallest counterclockwise rotation, hear the click sound that is off, clockwise rotation that is onProduct Use:Cell phones, laptops, tablets, sound signals through the 3.5mm sound cable connected to the stereo amplifier outputPackage List1 x Mini Amplifier Board1Button Control: Stereo mini amplifier board, high transmission effect and stability, with button control, convenient to control volume up and down, switch on and off, etc. 2Power Supply: This mini amplifier board uses micro 5p interface power supply, ordinary cell phone charger 5V 2A charging cable can be used (not included), convenient and fast. 3Output Interface: Amplifier module has two sets of speaker output ports (one for left and one for right channel), and it is recommended to connect 4 ohms 5W50W speakers. 4Working Mode Switching: Professional amplifier module, can freely switch CLASS AB or CLASS D working mode according to sound preference and power matching. 5Easy To Use: Integrated power switch and volume knob, when the sound is adjusted to the minimum turn counterclockwise and hear the click sound that is off, turn clockwise to turn on. 6Applications: Sound power amplifier board device to adjust the volume through the switch, ideal for DIY speakers. Be widely used in store solicitation, home theater, speakers, etc.