A hex head cap screw is a six-sided bolt with a washer face on the bearing surface. Hex cap screws are commonly used in OEM applications where precise tolerances are needed. ASTM A193 Grade B8 Class 1 bolts are manufactured from an AISI 300 Series stainless steel. Bolts manufactured using this austenitic stainless steel require carbide solution treatment after the heading operation. Carbide solution treatment, also referred to as solution annealing, is a process in which fasteners are heated and then water-quenched to assure maximum corrosion resistance.