Product DescriptionThis kit includes two guide balls sized at 1 ½ inch and 2 inch that fit around a drill bit to keep it centered when drilling through wall cavities and prevent the bit from wandering off course. The device is designed specifically for use with 3⁄16 inch shaft flexible auger bits and gives installers better control during drilling by stabilizing the bit and reducing the risk of damaging nails hidden in studs or patching walls and carpeting due to errant drilling. It is ideal for low voltage installations, structured wiring, security system cable pulls and any project where clean, accurate hole placement through drywall or plaster is required.