ANSI Hex Socket Screw

ANSI Hex Socket Screw with a tensile strength of 170,000 psi, these alloy steel screws are stronger than Grade 8 steel screws. Black-oxide steel screws are mildly corrosion resistant in dry environments. Zinc-plated steel screws resist corrosion in wet environments. Zinc-aluminum-coated steel screws are 40 times as corrosion resistant as zinc-plated screws and comparable to Magni-coated screws. They withstand 1,000 hours of salt spray per ASTM B117. Coarse threads are the industry standard; choose these screws if you don't know the pitch or threads per inch. Fine and extra-fine threads are closely spaced to prevent loosening from vibration; the finer the thread, the better the resistance. They are not compatible with coarse threads. Screws that meet ASTM A574, ASTM A574M, and ISO 898-1 comply with specifications and testing requirements for material quality. Screws that meet ASME B18.3, ASME B18.3M, ISO 21269, and ISO 4762 (formerly DIN 912) comply with specifications for dimensional standards.