Works in cases of corrosion, rounded lug heads, thin walls for specialty aluminum wheels, etc. Works on at least 6 different fastener types: Spline, 6-Point, 12-Point, Star, Square, 50% Rounded Off Heads. Manufactured using quality Chrome Molybdenum alloy steel for high-torque and durability. Color-coded protective sleeves for easy identification which helps to prevent damage to custom wheels. Impact rated. 1/2 in. Drive Socket Sizes Include :17mm 19mm 21mm. Non slip design helps protect sockets / drive up tp 70% rounded off nuts. All centrifugal power sockets use the same interchangeable disc. Over 40% more busting power.