1. The function of the soft start board is to reduce the impact of the machine on the power grid and extend the lifespan of the switch by reducing the instantaneous impulse current during startup 2. This board uses a super high current (100A) pure copper relay and a super large thermistor 20D-20, effectively protecting the machine from excessive startup current 3. This board does not require auxiliary power supply, only has 2 wiring terminals, one connected to the power input (previously connected to a switch control), and one output connected to the load, making it very convenient to use 4. On the market, the discharge resistor is omitted for the soft start with power amplifier and high-voltage capacitor, which makes it extremely unsafe for the soft start circuit board to remain live even after unplugging the power plug. As a result, the plug is live and can easily harm family members. This circuit board is equipped with a safe discharge resistor, which can be used with confidence 5. This product is not suitable for soft start of low-power devices such as 40W, 100W, 200W, and 300W. It belongs to high current soft start, and provides a soft start current of around 300-400W at the moment of power on. The relay engage and conduct conduction in about 3 seconds Color:As shown Material:Aluminum + Metal Package Contents: 1 * High frequency filtering module Only the above package content, other products are not included. Note: Light reflection 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.