Doweling Jig Guide And Clamp Assembly Allows For Easy Dowel Hole AlignmentSpring Positioning Revolving Turret Doweling Jig Ensures That The Dowel Holes Are Located Accurately And Drilled SquarelyRevolving Turret Accepts 6 Sizes Of Twist Or Brad Point Drill Bits: 3/16", 1/4", 5/16", 3/8", 7/16" And 1/2"Clamp System Works On Stock Up To 4"Clamp Screws Firmly Locks Tool In Position On Work PiecesConstructed Of Rust Resistant Metal And Glass Reinforced NylonKit Includes: 1 Doweling Jig, 3 Brad Point Drill Bits (1/4", 5/16" And 3/8"), 8 Piece Dowel Center Set (1/4", 5/16", 3/8" And 1/2"), 3 Drill Stops (1/4", 5/16" And 3/8"), 10 Each Dowel Pins (1/4", 5/16" And 3/8") And Wood Glue