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SPAX PowerLag 5/16 in. in. X 3 in. L T-40 Washer Head Serrated Structural Screws
SPAX PowerLag 5/16 in. in. X 3 in. L T-40 Washer Head Serrated Structural Screws
SPAX PowerLag 5/16 in. in. X 3 in. L T-40 Washer Head Serrated Structural Screws
SPAX PowerLag 5/16 in. in. X 3 in. L T-40 Washer Head Serrated Structural Screws
SPAX PowerLag 5/16 in. in. X 3 in. L T-40 Washer Head Serrated Structural Screws
SPAX PowerLag 5/16 in. in. X 3 in. L T-40 Washer Head Serrated Structural Screws

SPAX PowerLag 5/16 in. in. X 3 in. L T-40 Washer Head Serrated Structural Screws

Made in America

Support American manufacturers + independent hardware retailers in one purchase.

A washer-head structural screw with serrated thread that bites into wood-to-wood joints without a pilot hole.
Spax MPN 45818208007643
Sold Locally Only

This product isn’t sold on our website — see your local hardware store.

In-Store Exclusive

This one's worth the trip to the store.

This Spax item is one you'll find in stores rather than online — and that's often the better way to buy. In store you get the genuine article, full manufacturer warranty, and real advice from someone who's actually handled it — no counterfeits, no gray-market resellers.

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About Product Overview

SPAX PowerLag structural screws are built for wood-to-wood connections that need to hold, from deck framing to structural repairs. The washer head seats flush and spreads load, while the serrated, self-tapping thread bites in without a pilot hole in most applications. A high corrosion-resistant finish means these hold up whether the job is inside or out.

  • Size: 5/16 in. x 3 in.
  • Head Type: Washer with T-40 drive, driver bit included
  • Material: Carbon steel, Grade 5, high corrosion resistant finish
  • Package: 12 count, clamshell

The Details Specifications

Brand Spax
Model / MPN 45818208007643
UPC 712216024304
Weight 1 lbs
Country of Origin USA
Safety Data Sheet (SDS) Manufacturer documentation · opens in new tab
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