Featuring SK's high polish SuperKrome® finish, which protects the tools from the harsh working environments found in today's workplace. Provides long life and maximum corrosion resistance. All sockets feature SK's SureGrip® hex design, which drives the side of the fastener, not the corner, to avoid edge breakage which can occur on rusted or damaged fasteners when a traditional straight cornered hex tool is used. 3/8 in. Drive, 6-Point Standard Fractional Socket - 5/16 in.