The GripEdge Tools 9-pc 1/4" Drive Long Star Driver Set, No. STA9LS, are precision machined from S2 steel for increased strength, durability, and corrosion resistance. The set includes sizes T6, T8, T10, T15, T20, T25, T27, T30, and T40, and each socket has a 4" overall length for increased access to confined spaces. The sockets feature Rounding Prevention Technology that provides more torque on new and damaged fasteners and prevents rounding. Each socket includes oversized and ink-filled size markings, and the set comes on an aluminum socket rail.