(1) we are not a switch will connect the wireless camera, and all products can support PAL or NTSC , But don't support PAL and NTSC at the same time.(2) Please choose a quality camera to connect. A bad camera cannot be identified by the control unit.(3) when the product is on, your screen is blue, the product will work properly.After installation, your camera does not work, please check the quality of your camera and your connection. Thank you.Four-channel car video controller with four-door partition, with a mirror switch for each cameraYou can see 4 camera images in one windowSize: 22.5MMImage Sensor: 1/4inch CCDTV system: NTSC(Default) or PALHorizontal Resolution: 580 TV linesPixels: 656(H) x 592(V)Sync. System: internalS Ratio: Greater than 48dBNight Vision: YesElectronic Shutter: 1/60 to 1/100,000 secondsVideo Output: 1.0Vpp, 750hmWhite Balance: AutoPower: DC 12VOperating Temperature: -40 to + 80 degree, 95% RH maximumStorage Temperature: -40 to + 105 degree, 95% RH maximuVideo Cable Length: about 6mMaterial:plasticcolour:BlackPackage Contents:1 x Camera Video Control1 x remote controlOnly the above package content, other products are not included.Note: Light 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.