HEAVY-DUTY LICENSE PLATE FRAME BACKUP CAMERA: Perfect for most of vehicles that use a standard US license plate. It is like a plate frame mounted on the license plate, holds the license plate securely without blocking the license plate info. Before buy, pls check your license plate size first GUIDE LINE ON/OFF: Cut the Green Line, the Guide Line will be disappear. If Guide Line no disappear, please check your monitor if set with guide line