ASTM A194 Grade 2H heavy hex nuts are intended for use in flange bolting applications, as well as structural applications and with other high strength bolting. ASTM A194 covers carbon steel, alloy steel, and stainless steel nuts for bolts in high pressure or high temperature service. Grade markings consists of both the grade symbol "2H" and the manufacturer's identification mark.They are a common high strength nut used mainly with A193 Grade B7 when PTFE coated. Dimensional specifications are governed by ASME B18.2.2. Heavy hex nuts provide increased bearing surface area over finished nuts such as J995 Grade 2 nuts. Available in hot dipped galvanized finish for corrosion resistance. PTFE coating (also referred to, in general, using the Dupont trade name Teflon) is formulated with superior characteristics for maximum fastener life. Technical components include a tensile strength of up to 4,000 psi and an operating pressure up to 100,000 psi. The absence of nut locking oxides enable easy and safe removal. PTFE coatings have extreme chemical resistance and are ideal for applications including insulating piping, boiler rooms, water filled piping, water lines and more.