Product description: Excellent noise suppression in the absence of the input audio ear horn can not hear any noise two channel stereo; 5V power supply and can output 3W+3W power and can directly drive 4 ohm 8 ohm speakers; Large output power energy sufficient good sound quality; Unique Class D digital power board without LC filter; Can be powered through USB of compute; Dual panel wiring wiring properly solve the crosstalk caused by ground potential balance and inter channel; Ultra micro design can be easily placed in a variety of digital products inside the small space; High amplification efficiency; Whole board soldering by machine far better than manual soldering; Note: Negative of left and right output port can not be connected in parallel otherwise it will burn IC connect the speaker (load) before power on; Rated voltage: 2.5~5V; Limit voltage: 5.5V