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SPAX PowerLags 5/16 in. in. X 6-3/4 in. L T-40 Washer Head Serrated Structural Screws
SPAX PowerLags 5/16 in. in. X 6-3/4 in. L T-40 Washer Head Serrated Structural Screws
SPAX PowerLags 5/16 in. in. X 6-3/4 in. L T-40 Washer Head Serrated Structural Screws
SPAX PowerLags 5/16 in. in. X 6-3/4 in. L T-40 Washer Head Serrated Structural Screws
SPAX PowerLags 5/16 in. in. X 6-3/4 in. L T-40 Washer Head Serrated Structural Screws
SPAX PowerLags 5/16 in. in. X 6-3/4 in. L T-40 Washer Head Serrated Structural Screws

SPAX PowerLags 5/16 in. in. X 6-3/4 in. L T-40 Washer Head Serrated Structural Screws

Made in America

Support American manufacturers + independent hardware retailers in one purchase.

A 250-count bucket of self-tapping structural screws with the T-40 bit included, built for wood framing that has to hold.
Spax MPN 3581820801710 In Stock & Ready to Ship
Local Price Check i Local stores may price this as low as $269.99. Our online price is $299.99.
$299.99
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

These SPAX PowerLags are built for structural wood-to-wood work, and the 5/16 x 6-3/4 in. size puts them squarely in framing and heavy timber territory. A 250-count bucket means you're not running short mid-job, and the washer head gives you a solid bearing surface without needing a separate washer.

The serrated thread design is self-tapping, so these bite into wood without requiring a pre-drilled pilot hole in most applications, saving setup time on multi-screw projects. Grade 5 carbon steel construction with a high corrosion-resistant finish means these hold up whether you're building outdoors or in. The T-40 drive style is included with the bucket, so you've got the right bit on hand from the first screw to the last.

Good fit for deck framing, post and beam connections, ledger boards, and other structural wood assemblies where you need a fastener that won't back out or shear under load.

  • Size: 5/16 in. x 6-3/4 in.
  • Drive style: T-40 (bit included)
  • Head type: Washer head
  • Material: Grade 5 carbon steel, black, high corrosion-resistant finish
  • Thread: Serrated, self-tapping (not self-drilling)
  • Packaging: 250-count bucket, rated for indoor and outdoor use

The Details Specifications

Brand Spax
UPC 712216024427
Case Pack Quantity 1 per case
Retail Unit Quantity 1
Dimensions (L × W × H) 10 × 10 × 8
Weight 21 lbs
Country of Origin USA
Safety Data Sheet (SDS) Manufacturer documentation · opens in new tab
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01

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02

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03

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04

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