Amazon.com With its durable SuperKrome finish, the SK Hand Tools 18-Piece SuperKrome Combination Wrench SuperSet stands up to harsh working environments. The high polish finish ensures long life and maximum corrosion resistance. All wrenches feature the SureGrip hex design, which drives the side of the fastener, not the corner, to avoid edge breakage. Box ends are also counter-sunk to help lead the wrench over fastener heads. The open end is angled 15 degrees for greater access. The handle edges are rounded for improved gripping and increased user comfort. This set comes with a lifetime warranty.What's in the Box 1/4-, 5/16-, 3/8-, 7/16-, 1/2-, 9/16-, 5/8-, 11/16-, 3/4-inch wrenches; 10-, 11-, 12-, 13-, 14-, 15-, 16-, 17-, and 18-millimeter wrenches. From the Manufacturer 18-Piece set is made in the U.S.A., featuring SK's high polish SuperKrome finish, which protects the tools from the harsh working environments found in today's workplace, while providing long life and maximum corrosion resistance. The SureGrip wrenching design on wrench box ends drives the side of the hex of the fastener, not the corner, to increase torque and avoid edge breakage, especially on rusted or damaged fasteners. Box ends are also countersunk to help lead the wrench over fastener heads. The open end is angled 15 Degrees for greater access. The box end design features a 15 Degrees offset head, which provides useful clearance and a smooth arc radius design for improved strength and durability. Handle edges are rounded for improved gripping and increased user comfort.