T-track Accessory Set - (2) Star Knobs & (2) 1/4-20" Bolts Star Knobs and Bolts Set - Great for Holds Downs and Jigs For use with ORANGE ALUMINUM OA7150 t-tracks 2 Star Knobs: (1.900 ODx1/4-20" ) female thread (Soft to the touch*) 2 Hex Head Bolts: 1/4"-20 x 1-1/2" Zinc Plated bolts