Features: This 400W monos sound Amplifier delivers powerful, high sound with A1943/C5200 power transistors, effortlessly driving 15 inch speakers for professional sound performances. Featuring a accuracy engineered double differential circuit (A970/C2240) and electric amplification stage (A1145/C2705), it operates across ±20V 90V with A1837/C4793 power transistors for stable 300W+ output. Ideal for audiophiles, sound engineers, and professional seeking robust amplification for large scale speakers systems or studio setups. Perfectly suited for home theater systems, live sound reinforcement, and large power sound applications requiring dynamics and minimal distortion. Engineered for outstanding clear and depth, this amplifier combines advanced thermal stability with strong plastic housing for long lasting performances in demanding environments. Specifications: Component : plastic Amplifier board size: about 195X60X45MM/8x2.4x2inch Actual power: 400W without distortion, greatest power of 600W. . Power supply: double electric , plus or minus 20-90V (upgraded version optimizes circuit and components, can Package Includes: 1xAudio Amplifier Board note: 1.Please allow 1-2cm errors due to manual measurement, make sure that you do not mind before you order. 2.Due to the difference between different monitors, the picture may not reflect the actual color of the item.