The DOYLE™ 12 in. High Performance Adjustable Wrench is precision machined for super-smooth operation and a tight grip on fasteners. The adjustment screw offers precise jaw fit to prevent slipping or rounding fasteners. Laser etched size markings make it easy to quickly adjust jaws for a perfect fit. The adjustable wrench is constructed from heavy duty chrome vanadium steel with a heavy duty chrome plate finish to protect against rust and corrosion.