Made to Japanese Industrial Standards, these Class 10.9 steel screws can be used in high-stress applications, such as valves, pumps, motors, and automotive suspension systems. They are at least 25% stronger than medium-strength steel screws. The flange distributes pressure where the screw meets the surface, eliminating the need for a separate washer. Head height includes the flange. Length is measured from under the flange.

Zinc-plated and zinc yellow-chromate plated screws resist corrosion in wet environments. They’re a good choice for most applications.

Black-oxide screws have a dark, matte coating for a finished look. They offer minimal corrosion resistance, so they’re best for dry environments.

Match the thread spacing of mating components. Coarse threads are the industry standard; choose these screws if you don’t know the pitch. Fine and extra-fine threads are closely spaced to prevent loosening from vibration; the finer the thread, the better the resistance.