The Snap-on Industrial Williams Flextensions, built for technicians who work extensively with engine and heavy equipment, feature an integrated (non-removable) drive extension and socket design. The Williams Flextensions help increase productivity by allowing reliable, continuous workflow without concern for the socket disconnecting from the extension. Available in a wide variety of both SAE and Metric socket sizes and extension lengths, in both 1/2” and 3/8” square drives, most are available in “Tension” and “Non-Tension” models. These tools offer a black oxide finish, lobular openings for increased turning power, up to a 30-degree angle offset and more. The Williams Flextensions are designed for hand and power tool use, not for impact tool use.