?FEATURES:The Heavy-Duty Solution for Building with WoodCreates joints 50% stronger than standard Kreg JointsOptimized for large outdoor projectsFor use with materials 11/2? thick (38mm) and thickerWorks with the Kreg Jig??K5, K4, and K3Stop Block provides easy, repeatable registration to workpieceFace Clamp locks into Kreg Jig HD for secure drillingHex-Shank HD Drill Bit is Quick-Change compatible