supply: DC supply +/- 58-+/- 70VThe rated output : 500W (+/- 65V supply, 4 ohm load, distortion 10%)Efficiency: greater than equal 90%SNR: 90dBFrequency range: 20Hz-20KHzMaterial: CCLColour: blueThe harmonic distortion:380W (+/- 65 4 ohm speaker, distortion Less than 0.1%)280W (+/- 65 8 ohm speaker, distortion Less than 0.1%)Speaker: 4-8ohmVoltage Magnification: 36 timesInput sensitivity 1.5V ()Output short circuit protection: YesThat output DC bias protection speaker protection: YesOver-temperature protection: Yes, radiator FET temperature higher than 100 Celsius , turn off the outputProduct Size: approx. 100 x 50 x 30mm/3.93" x 1.96" x 1.18"Net weight: approx.100gPackage Includes:1 x Digital Amplifier ModuleNote: Light 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.