Feature:1. With output short circuit protection, this AMP board can be easy to use in the practical life.2. Amplifier module supports output DC bias protection and speaker protection, which makes itself getting great popularity.3. Over temperature protection means that the output will turned off when the temperature of the heat sink FET is higher than 100 C.4. Easy to use in the practical life, such audio parts supports simple installation, practical.5. After many inspections before leaving the factory, such circuit board quality is guaranteed, you can use it with confidence.Specification:Item Type: AMP boardPower Supply: DC dual power supply 58 70vRated Output Power: 500w ( 65v power supply, 4 ohm load, 10% deformation)Efficiency:> 90%Signal to Noise Ratio: 90dbTotal Harmonic Distortion:380w ( 65 power 4 ohm speaker, distortion <0.1%)280w ( 65 power 8 ohm speaker, distortion <0.1%)Frequency Range: 20Hz-20kHzSpeaker: 4-8ohmVoltage Magnification: 36 timesInput Sensitivity: 1.5v (RMS)Output Short Circuit Protection: YesOutput DC Bias Protection Speaker Protection: YesOverheat Protection: Yes, the temperature of the radiator is higher than 100 C, turn off the output!Product Size: Approx. 100 x 42 x 35mm / 3.94 x 1.65 x 1.38inNet Weight: Approx. 100 g / 3.5 oz.Package List:1 x AMP Board