The blades of the entire range of allen keys are forged from chrome vanadium steel which has undergone a high frequency heat treatment in order to achieve a hardness of between 160 and 180kg/mm². The quality of this steel allows a reduction in the thickness of the resulting key, meaning that after the insulation process the Clydesdale range of keys is comparable in thickness to other non insulated keys of the same usable size. The tightening torques achieved by Clydesdale keys are greater by approx. 60% than those specified by the nut and bolt industries by their standards worldwide.

Metric Sizes