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Prime-Line 9055857 Hex Lag Screws, 5/16 In. X 4 In., A307 Grade A Hot Dip Galvanized (15 Pack)

Free shipping on orders over $29.99

$10.67

$ 5 .99 $5.99

In Stock

1.Size:5/16 In. -18


About this item

  • Size: 5/16 inch X 4 inch
  • Heavy duty wood screw with 6 sided hex bolt head
  • Features deep wood screw threads and does not accept a nut
  • Used in applications where standard wood screws cannot support the load (deck building, etc.)
  • Requires pilot hole to be drilled and installs using wrench or socket tool
  • Thread Type: Deep, Point Style: Gimlet
  • Specification(s) Met: ASME B18.2.1 and ASTM A307A


Lag screw bolts are used in place of standard wood screws whenever the mounting surface must bear a heavy load. The hex head allows for lag screws to be tightened with more torque than can be used on Phillips head screws, though a pilot hole is still required prior to installation. Note that lag screws do not accept nuts as they are technically thick heavy duty wood screws with threads designed to cut into wood. They are ideal for use on decks since installation can be accomplished without having access to both ends of the fastener, as opposed to standard hex bolts that require a nut on the opposite end.


Will's Deals
August 1, 2025
Quality built. I used 4 of these with washers to hang 4 bicycles on two 2”x4”s in my garage. Solid
bean
July 26, 2025
When a long bolt is what you want, this is for you. Especially when that length is the length that this particular bolt is. It is perfect! Plus it’s the perfect color of gray. If that color is what you love. Which is the color I love. So you should too. Buy 1. Or 100. Up to you. Bolt!
Julian Granberry
July 23, 2025
As advertised
Diane Howle
July 12, 2025
Quick delivery
willdesign
June 23, 2025
Not as heavily zinc coated as others I've used but seems OK.
james j dillabough
March 8, 2025
I like they worked for the job.
BC Atkins
December 30, 2024
Bolts were as described. would buy again
David S.
December 5, 2024
Watch out, I had several break without a lot of torque.