IBV4310 Features: * Internal torx impact driver * Made of high quality steel (chrome-molybdenum) * Made to transfer the pressure from the thinnest part of the socket wall toward the thicker section, resulting in increased strength * One piece socket * Each impact socket features high torque drives Construction: * Engineered specifically for use with impact tools, using the most up to date industrial specifications Dimensions: * 3/8"" Drive x T20 Warranty: * Lifetime warranty