KHE Rotor Sprocket High strength 7075-t6 aluminum made in Germany Cnc machined to tightest tolerances with exclusive ''diamond cut'' patented process which work-hardens the teeth and enhances durability Advanced tooth design for better support of the chain and super smooth running and hard anodized for extreme long life Sizes: 18t, 20t, 25t, 28t, 30t , 33t , 36t; accepts both 1/8 and 3/32 chains Weight: 25t (64g - 2.25oz ), 28t (76g - 2.68oz), 30T (86g - 3.03oz), 33T (110g - 3.88oz), 36T (122g - 4.30oz), Color: hard anodized black