Fits D Series connecting bar. The hole spacing is 2″ center to center for a 1/4″ socket head cap screw. Split clamp design grips the dovetail bar along the entire surface of the saddle and will not dent or scratch the dovetail bar. Features two large locking hand knobs for tool free operation, spring loaded jaws, anodized aluminum and stainless steel construction. 7″ Long, 4″ Wide, .75″ thick, Wt. 26 oz.