5/16 in. x 3-1/8 in. RSS T-30 Washer-Head Coarse-Thread Self-Drill Yellow-Zinc Structural Wood Screws (500 Pack) | GRK-10221

GRK Fasteners' T-30 RSS Washer-Head Coarse-Thread Self-Drill Yellow-Zinc Structural Wood Screws feature a yellow-zinc coating that provides enhanced corrosion resistance for interior and exterior applications where moisture exposure is a concern. The self-drilling tip reduces the need for pre-drilling, improving jobsite efficiency and minimizing material splitting. Designed for structural applications, these screws deliver consistent holding power in timber framing, deck construction, and heavy carpentry work. Their engineered design supports repeatable, professional-grade results in both new builds and renovation projects.

• The T-40 star-drive recess improves torque control and reduces stripping during installation
• The washer head design increases bearing surface for stronger structural fastening
• Self-drilling tip helps eliminate pre-drilling and reduces wood splitting
• Its coarse-thread design enhances grip and pull-out resistance in wood materials
• The yellow-zinc coating provides corrosion resistance for indoor and outdoor use