These alloy steel screws have a tensile strength of 170,000 psi, which makes them almost two and a half times stronger than stainless steel thread-locking screws and stronger than Grade 8 steel screws. In arid conditions, their black-oxide coating offers a moderate level of corrosion protection. Friction is added by a nylon patch that is glued to the threads to prevent loosening from vibration. Although screws can be reused, each usage reduces their gripping power. Under the head, the length is measured.

If you are unsure of the pitch or threads per inch, go with the industry standard coarse thread screws.

ASTM A574-compliant screws adhere to material quality tests and specification requirements. ASME B18.3 and ISO 4762 (formerly DIN 912)-compliant screws adhere to dimensional standards.