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Prime-Line 9055859 Hex Lag Screws, 5/16 In. X 4 In., A307 Grade A Hot Dip Galvanized (50 Pack)

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$48.79

$ 23 .99 $23.99

In Stock

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.


joseph63
Reviewed in the United States on July 15, 2023
I priced these at the local big-box home improvement store and for 50 it would have been a little over 82 bucks. If you have never used lag screws before, be sure to pre-drill a hole with a slightly smaller diameter before installing them.
tlowecats
Reviewed in the United States on June 3, 2021
Did a good job for my boat dock. Some were a little rough and difficult to fit in socket, but I got them all to work. I would recommend them.
Customer
Reviewed in Canada on November 7, 2021
priced right
Steve
Reviewed in the United States on January 21, 2020
Nice value but be careful not to over torque or they WILL snap