Renthal ultralite bmx sprocketborrowing technology from renthals championship winning motocross sprockets they have designed and developed these chainrings to offer the ultimate combination of lightness strength and durability renthal ultralite chainrings are designed to let you ride faster jump further and last longer features computer aided ultralite design enables the ultimate combination of strength and lightness high strength 7075 t6 aluminium alloy provides excellent longevity pr