Regina Chain 520 ZRD Chain and Sprocket Kit - 520 Conversion Kit 5ZRD/108-KHO018 Front sprocket, rear sprocket and a precut chain make a convenient kit for the dealer or consumer Sprockets have OEM gearing Chain is Reginas high-performance Z-ring series with gold outer plates and Z40 sealing rings, which dramatically improves performance and wear life; includes both clip- and rivet-type masterlinks 520 conversion kits include all the above, but the rear sprocket is aluminum rather than steel, which in some applications reduces the chain + sprocket weight by as much as 2.5 lb. Gearing: 16/43