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SPAX PowerLags 5/16 in. in. X 8 in. L T-40 Washer Head Serrated Structural Screws
SPAX PowerLags 5/16 in. in. X 8 in. L T-40 Washer Head Serrated Structural Screws
SPAX PowerLags 5/16 in. in. X 8 in. L T-40 Washer Head Serrated Structural Screws
SPAX PowerLags 5/16 in. in. X 8 in. L T-40 Washer Head Serrated Structural Screws
SPAX PowerLags 5/16 in. in. X 8 in. L T-40 Washer Head Serrated Structural Screws
SPAX PowerLags 5/16 in. in. X 8 in. L T-40 Washer Head Serrated Structural Screws

SPAX PowerLags 5/16 in. in. X 8 in. L T-40 Washer Head Serrated Structural Screws

Made in America

Support American manufacturers + independent hardware retailers in one purchase.

One fastener does the job of multiple bolts, with a self-tapping thread that skips the pre-drilling step.
Spax MPN 4581820802035
Sold Locally Only

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

Typical Store Price i
Typical store price: low $84.99, average $99.99
In-Store Exclusive

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About Product Overview

SPAX PowerLags are built for wood-to-wood connections that need to hold, whether that's timber framing, deck ledger boards, or heavy post-to-beam work. At 8 inches long and 5/16 inch in diameter, these Grade 5 carbon steel screws replace multiple structural bolts or lag screws in a single fastener, cutting install time without cutting strength.

The serrated thread bites into wood fast and self-taps, so there's no need to pre-drill in most applications. A T-40 washer head spreads clamping force over a wider area, and the included driver bit means you're ready to drive as soon as you open the box. The high corrosion-resistant black finish holds up whether the screws end up buried in an exterior deck frame or inside a wall.

  • Length: 8 in. / Diameter: 5/16 in.
  • Grade 5 carbon steel construction
  • Serrated, self-tapping thread
  • T-40 washer head with included driver bit
  • High corrosion-resistant black finish, indoor/outdoor rated
  • Boxed, 50 screws per package, made in USA

The Details Specifications

Brand Spax
UPC 712216023161
Case Pack Quantity 2 per case
Retail Unit Quantity 1
Dimensions (L × W × H) 4 × 10 × 3
Weight 5 lbs
Country of Origin USA
Safety Data Sheet (SDS) Manufacturer documentation · opens in new tab
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