SABRE Car Parking Assist Sensor detects distance between Car and Wall at 1, 2, or 3 Feet PRACTICAL & INNOVATIVE  the parking sensor detects the distance between your vehicle and garage wall to protect your vehicle and belongings from damage  an ideal complement to a vehicles backup sensor USER-FRIENDLY  tells you when to slow down and stop with yellow and red indicator lights; choose from 3 stop zones - 1, 2 or 3 feet EASY INSTALLATION  no wiring need; velcro strips (included) allow you to mount the sensor on a wall, workbench, refrigerator or just about anywhere in your garage (requires 4xAA batteries, not included) EXTRA LEVEL OF SECURITY  provides battery status update with low battery indicator MAXIMIZES SPACE - allows you to fit more items in your garage and takes the guessing out of where/how to park