Our 3/8 in drive metric 6-point socket with FOUR FLAT™ sides was designed from the ground up to be part of the most versatile socket family. Milwaukee® 3/8 in drive sockets feature an innovative design with four parallel flat sides, which deter rolling and are wrench compatible. The metric socket sizes are stamped into the flats providing you with improved, easy-to-read visibility. These deep and standard socket sizes have optimized geometry to reduce bolt rounding and stripping. We back all our 3/8 in drive metric sockets with a lifetime guarantee. Our 3/8 in drive metric sockets range from 6 to 19 mm in standard and deep well sockets.