Kreg Jig HD Pocket Hole Guide Creates joints 50% stronger than standard Kreg joints. Optimized for large outdoor projects. Stop Block provides easy, repeatable registration to work piece. Face clamp locks into Kreg Jig HD for secure drilling. Hex-shank HD drill bit is quick-change compatible. 1-7/16 drill guide spacings. Works with the Kreg Jig K3, K4, K4MS, and K5. Body Material Glass-Filled Nylon, Drill Guides 2 1/2 Dia Heavy-Duty, Clamp Type Face Clamps, For Use With 1-1/2 In. and up Thick Materials, Pkg Qty 1, Package Type Box Warning This product can expose you to chemicals including Acrylonitrile and other chemicals which is known to the State of California to cause cancer and reproductive harm. For more information go to www.P65Warnings.ca.gov.