Features: The power amplifier board uses TDA7377 integrated chip, high power, stereo dual-channel output 33w+33W. High power, good sound quality, for bookshelf speakers, floor-standing speakers. The wiring is very simple, you can use it by referring to the wiring diagram, and it is the first choice for beginners. It is portable power amplifier board for home computers, motorcycles, for car... You can adjust the volume knob to your liking.. Specifications: Size: approx 80 × 55 × 52mm -3.15x2.17x2.05in Output Power: 33W + 33W Power: DC12V 2A/ 50-100W Channel Type: Stereo 2.0 Frequency response: 20Hz-20KHz Supporting speakers: 4-8Ω20-120W speakers, Acoustic speakers Package Includes: 1PC TDA7377 35W+35W Dual Channel Amplifier Board note: Due to the problems of lighting effects and shooting angles, there will be certain tolerances in the product, please understand. Please allow 0-1cm error due to the manual measurment.