WMS Tuck & Run Sprockets are precision machined, lightweight, and proven winners. Whether you prefer the traditional "full tooth", or "skip tooth", the Tuck & Run Sprocket will give you an edge over the competition. High quality aluminum racing gears. Lightest and most aggressive sprocket on the market! Hard coated Fits 5 1/4" standard hub pattern Lightened design .160" thick for extra durability