The use of high-speed SMT placement machine， over temperature reflow， the performance is very stable，With 4 model GAIN parts.can auto work on different voltage.Ultra-small 70X57MMComes with super output short-circuit and over-temperature overload and prevent the impact of the switch machineSTMicroelectronics TDA7492 chip.low price. but with big power and good sound quality output Note: When the speaker impedance is 4 ohms， the operating voltage must be less than 18V， the speaker impedance is 6 ohms， the operating voltage can not exceed 24V， the speaker impedance is 8 ohms， the working voltage can not exceed 26V， the power not to reverse the polarity. Specification:Power supply: Single-voltage 10-26V DCMaximum power:50W*2/8OhmMono BTL power 100W / 4 OhmsSize:70*57mm*21mm