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HILLMAN 3/8 in. X 5-1/2 in. L Hex Hot Dipped Galvanized Steel Lag Screw 50 pk

Made in America

Support American manufacturers + independent hardware retailers in one purchase.

Hillman 3/8 in x 5-1/2 in Hex Lag Screw — a rugged exterior-grade fastener designed to secure thick wood joints with confidence. Coated in a hot-dipped galvanized finish for lastin…

Hillman MPN 812078 In Stock & Ready to Ship
Local Price Check i Local stores may price this as low as $63.99. Our online price is $70.99.
$70.99
Includes free shipping on orders over $75 · $8.99 standard below
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About Product Overview

Hillman 3/8 in x 5-1/2 in Hex Lag Screw — a rugged exterior-grade fastener designed to secure thick wood joints with confidence. Coated in a hot-dipped galvanized finish for lasting corrosion resistance, it stands up to moisture, rain, and outdoor use without rusting or losing strength.

  • Size and construction: 3/8 inch diameter, 5-1/2 inches long; steel lag screw with coarse threads that bite into wood for strong holding power.
  • Drive and head: Hex head accepts standard hex drivers or sockets for solid, high-torque driving and easy removal if needed.
  • Finish and durability: Hot-dipped galvanized coating provides durable protection against corrosion in exterior environments.
  • Package and convenience: 50-count box, making it ready for large projects or multiple jobs without frequent repurchases.
  • Best uses: Ideal for attaching thick lumber in decks, fences, pergolas, railing systems, and other outdoor structures; suitable for wood-to-wood joins where extra withdrawal resistance is required. For hardwoods, predrilling is recommended to prevent splitting and to achieve optimal bite.
  • Why choose this Hillman lag screw? It combines a robust 3/8 in diameter with a long 5-1/2 in reach, giving you the leverage and grip needed to fasten heavy framing securely, while the galvanized finish lowers maintenance and replacement over time.

The Details Specifications

Brand Hillman
SKU 56131
UPC 008236133196
Unit 0
Case Pack Quantity 2 per case
Retail Unit Quantity 1
Unit of Measure 50 BX
Dimensions (L × W × H) 7 × 5 × 3
Weight 9 lbs
Cubic Feet 0.1016 ft³
Country of Origin USA
Safety Data Sheet (SDS) Manufacturer documentation · opens in new tab

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