ROK Pocket Hole Drilling Jig Kit System with Bushing, Drill bit and Stop Collar Adjustable with double holes, Ideal to make precise pocket holes Just clamp the drill guide to each piece being joined, mark off the location and depth, drill holes in each then screw together Kit includes:Cast aluminum jig, 3/8" drill bit, Stop collar, 4 Bushings Use to join table legs, table tops, cabinet frames etc