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GRK Fasteners 5/16 in. in. X 3-1/8 in. L Star Washer Head Self Tapping Structural Screws
GRK Fasteners 5/16 in. in. X 3-1/8 in. L Star Washer Head Self Tapping Structural Screws

GRK Fasteners 5/16 in. in. X 3-1/8 in. L Star Washer Head Self Tapping Structural Screws

Self-tapping W-Cut thread and a star-drive hex head give these structural screws serious holding power for deck and framing work.
Grk Fasteners MPN 10221 In Stock & Ready to Ship
Local Price Check i Local stores may price this as low as $296.99. Our online price is $329.99.
$329.99
Free shipping on orders over $149
Ships within 24 hours · most orders arrive in about 2 business days
Ships free on orders over $149 $14.99 flat shipping until your order reaches $149.

About Product Overview

GRK's 5/16 x 3-1/8 in. structural screw is built for wood-to-wood connections that actually carry weight - ledger boards, deck framing, beams, posts, and other load-bearing joints where a standard deck screw won't cut it. The W-Cut thread taps its own path as it drives, so you get strong holding power without pre-drilling on most jobs, and the hex head with star drive gives you a solid bit connection for high-torque driving without stripping.

Climacoat finish is rated for indoor and outdoor use, so these hold up on exposed structural work as well as framing tucked inside a wall. Each box holds 500 screws, enough to keep a crew stocked through a deck build or a full framing job without running back to the store mid-project.

  • Size: 5/16 in. diameter x 3-1/8 in. length
  • Head Type: Hex with Star drive
  • Thread Type: W-Cut, self-tapping (not self-drilling)
  • Finish: Climacoat, rated for indoor and outdoor use
  • Material: Steel
  • Package: 500 screws, boxed

The Details Specifications

Brand Grk Fasteners
UPC 772691102218
Case Pack Quantity 1 per case
Retail Unit Quantity 1
Dimensions (L × W × H) 10 × 10 × 5
Weight 16 lbs
Country of Origin TAIWAN
Safety Data Sheet (SDS) Manufacturer documentation · opens in new tab
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