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HILLMAN 5/16 in. X 3-1/2 in. L Hex Hot Dipped Galvanized Steel Lag Screw 50 pk

Made in America

Support American manufacturers + independent hardware retailers in one purchase.

Hot-dipped galvanized steel and a hex head built to handle outdoor lumber connections without rusting out.
Hillman MPN 812045 In Stock & Ready to Ship
$34.99
Free shipping on orders over $75
Ships within 24 hours · most orders arrive in about 2 business days

About Product Overview

These 5/16" x 3-1/2" hex lag screws from Hillman are built for outdoor and structural work where corrosion resistance matters. The hot-dipped galvanized finish stands up to moisture and weather, making them a solid choice for deck framing, fence posts, and other exterior lumber connections. The hex head gives you a solid grip for a wrench or socket when you need real torque, and the coarse thread bites deep into wood for a strong hold. Comes boxed for easy storage and job-site transport.

  • Size: 5/16" x 3-1/2"
  • Finish: Hot dipped galvanized
  • Head type: Hex
  • Thread type: Coarse
  • Material: Steel
  • Package: 50 count, boxed

The Details Specifications

Brand Hillman
Model / MPN 812045
UPC 008236133042
Weight 4 lbs
Country of Origin USA
Safety Data Sheet (SDS) Manufacturer documentation · opens in new tab
Price check

Go ahead. Check.

You're going to price-check us against Amazon, Home Depot, and Lowe's. Everybody does. Good — open all three tabs. We'll wait. Then look hard at what you're actually being handed over there.

On Amazon, start with these four questions before you click buy.

01

Who's actually selling it

The brand name is on the listing. A different company is in the seller field. Those aren't the same thing, and the second one is who you're buying from.

02

Whether the warranty survives

Most manufacturers only honor a warranty when the unit came through an authorized dealer. We're authorized for Hillman. A third-party marketplace seller usually isn't.

03

Where the box came from

Gray-market stock, returns repackaged as new, and outright fakes move through marketplaces constantly. It all looks identical in the photo. It stops looking identical when it fails.

04

Who you call when it breaks

Ours is a phone number with a person behind it who has held this product. M–F, 6 AM – 5 PM Pacific. (866) 469-8556

The big boxes don't care if your hardware store survives.

Amazon, Home Depot, and Lowe's are built to pull every hardware dollar out of your town. When the local shop can't keep the lights on, the counter where somebody actually knew which part you needed goes with it. We're built the other way: real brands so you're never stuck on a marketplace, and a straight answer to buy it down the street when that's the better call. Support independent hardware — it doesn't restock itself.

Why we tell you to shop local
Authorized dealer · Hillman

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