Set Screw wrenches are drop forged from steel bar. These wrenches are available in fractional sizes only from ?" through 5/8". These industrial black wrenches are machined to industry standards. These are special purpose Double Head Open End wrenches with 22-1/2 degree angled slotted openings at each end. The 3-point contact openings are of different convenient sizes with additional head thickness to accommodate the greater head height of square head set screws. Generally used for jigs, fixtures or machine tools which require frequent adjustment of square head set screws.