①. The built-in rear power filter can effectively supply stable 12V DC power to the rear camera, which helps to solve the problem of "screen flickering" or "black screen" when reversing with the rear camera. It is a camera rectifier with stable performance. ②. The 12V power relay filter rectifier can be used to supply stable 12V DC power to the rear camera. It is a car rectifier for German/American car series. ③. This rear camera filter is made of precision parts, plastic housing and sturdy structure. Waterproof design, good wear resistance and long service life. Easy installation without modification, cutting or drilling: Red line input: positive pole of the reversing light. Black line input: negative pole of the reversing light. Red line output: positive pole of the camera. Black line output: negative pole of the camera. ④. Material: Plastic shell. ⑤. Applicable: Applicable to German/American cars. ⑥. Package Contents: 1 x Power Relay Capacitor Signal Filter. ⑦. Notes: 1. Due to the different display and lighting effects, the actual color of this item may be slightly different from the pictures. Thank you! 2. For manual measurement, please allow 0-1cm measurement deviation.