Our advanced opening profile places more metal in high-stress areas to stiffen the jaws, increase tool strength and reduce permanent jaw spread—now a standard feature on all wright open-end and combination wrenches. Precision placed protrusions are custom engineered for each wrench size to keep it seated on the fastener, increase torque and reduce slippage.

https://www.wrighttool.com/products/wrenches/combination-wrenches-12-pt-flat-stem/12-pt-flat-stem-combination-wrenches-satin-finish