1). One stage for RFI filter DC circuit, through two 50A bridge stack and four 35V2200UF capacitors, filter the DC component of the AC power supply to suppress the magnetic saturation or static current increase due to the DC component transformer, resulting in hum. 2). Differential mode filtering, two differential touch inductors, differential mode filtering of the AC power supply to suppress high and medium frequency interference 3) First-level common-mode filtering, through X2 capacitors and common-mode inductors, combined into common-mode filtering. (4) Two common mode filtering, because of the use of two stages (also known as two sections) filtering, so the filtering of noise better. For some users there are fast transient group pulse interference with a repetition frequency of several kilohertz, can play a suppression role. Input voltage: single-phase AC 110--250V Output voltage: Single-phase AC 110--250V Load rated current: 4A--20A Input port: Three-wire 7.62 socket input Output port: 2-wire 7.62 socket output Colour:As Shown Material:plastic+metal type:20A Package Contents: 2 x Power Filter Board Module