INCRA Build-It Knobs, 1/4-20 by 1-1/2-Inch Bolts, Washers, Set of 8 Work with all INCRA Track and INCRA T-Track components and accessories Allows for easy attachment of user made stops and accessories Attach stops to the T-slots connector Includes fasteners for material up to 1-inch thick. Set of eight covers a wide range of needs