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Stainless Steel Hex Lag Screw - 3/8"

Stainless Steel Hex Lag Screw - 3/8"

Item # FA74521
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  • Reviews (65)
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Fastenal Accessories and Parts - FA74521

  • Trailer Fenders
  • Screws
  • Fastenal

  • Diameter: 3/8"
  • Length: 1-1/4"
  • Wrench size: 9/16"

74521 Fastenal Stainless Steel Hex Lag Screw

Video of Stainless Steel Hex Lag Screw - 3/8"

Videos are provided as a guide only. Refer to manufacturer installation instructions and specs for complete information.

Video Transcript for Review of Fastenal Trailer Fender Parts - Stainless Steel Hex Lag Screw - FA74521

Ellen: Hey everybody. I'm Ellen here at and we're going to be taking a quick look at these stainless steel hex lag screw.This helps to make sure that you can attach any kind of material that might be under a heavy load. That's typically where you're going to want a lag screw. It is a very sturdy, well-built screw. Has a three three-eighths inch diameter, so you'll want to make sure that you drill out a pilot hole that matches that. The length is 1-1/4 inch.So 1-1/4 inch there and the wrench size that will work with this up at the top is 9/16 of an inch.That's pretty much all there is to it for our look at the stainless steel hex lag screw.If you need any other hardware or other accessories, we have a lot of options available here at

So check them out.Thanks for watching.

Customer Reviews

Stainless Steel Hex Lag Screw - 3/8" - FA74521

Average Customer Rating:  4.9 out of 5 stars   (65 Customer Reviews)


Perfect stainless steel lag screw for bunk board installations


No problem


Worked great with the rubber numbers


I used the ss hex lag screws and CE Smith swivel brackets to replace the bunk boards on my bass boat trailer. Both items have performed well with no issues. I expect to get years of service from them. I have purchased many products from Etrailer and have received excellent customer service and timely delivery.


Everything came in as advertised. Purchased CE Smith bolsters, u-brackets, lag screws and carpet. Added two bunk boards to my Lowe trailer (Karavan). Only had two boards and I wanted extra to support the weight of the boat. Everything assembled easily. My boat loads easier and trailers better. Plus I have the piece of mind of having 4 boards vs 2.


Exactly the parts I was looking for, and for a price that couldn't be matched. The cost with shippping was less than just the parts at other places. I ordered 3 rubber bumpers for the tailgate of my toy hauler, along with the necessary mounting hardware. Shipping confirmation the same day.
I kept checking the shipping tracking number and expected the package in about 8 days. It actually arrived 2 days early. (economy shipping chosen)
Great service from etrailer.


Great service great product. Fast deli very.


Fit and work great. Quality!


much better holding power than the 1/2 lag screws the 3/8 lag screws replaced . with stainless steel screws and washers , no worries about replacing them .


Excellent product, great price and fast shipping


I used these fasteners to attach the swivel brackets to my bunk boards on my bass boat. Excellent product and competitive price. These could not be found locally and what I did find locally was not acceptable.


I ordered two rubber pads with lag screws and washers for a trailer ramp. The order arrived within a very reasonable time frame. I was pleased with the order, the service, and the merchandise. Definitely will do business again.


Local sport goods does not carry but up to two inch brackets this company had everything I needed and followed up with E-mail to ensure my brackets and screws that order were receive in proper time frame and that I was happy with product. I found this type of customer service very rare in today's time. God bless this business for being different.


I used the SS lag screws to secure my boat trailer bunk boards to the trailer frame. The price was great and shipping was fast.


eTrailer had the parts i needed at the best price I could find after researching numerous places. The order was practically shipped immediately and arrived within a few days. They even followed up byu email to confirm delivery and to make sure I received exactly what I wanted/needed.


I have been please with all products I have purchased through etrailer


Everything in the order came exactly as represented, received in a couple of days, and the best pricing I found. On a 1 to 10 scale, I give etrailer 12.




Fit were I wanted to put it.


Bolts are of good quality and are what I was looking for to install my trailer boards.


Great product and easy installation! Would buy from them again!


Easy to order from website, quick delivery after order, quality products received! Great experience!


Thank you for getting the product to me in a very timely manner. It was pakaged the best I have ever seen. I was very impressed by the way it was shipped. Thank you again, it's always great to do business with you. Bob j


Great service and delivery parts worked great.


Exactly what I needed.
Items fitted
Order was tracked with precision.

Show More Reviews

See what our Experts say about this Fastenal Accessories and Parts

  • What Size Bolt to Use with Rubber Bumper for Enclosed Trailer Ramp Door # 37210715
    The hole diameter of the Rubber Bumper for Enclosed Trailer Ramp Door # 37210715 is 3/8 inch so you'd want to pick a screw or bolt with that diameter to fit the best. We have a 3/8 inch diameter lag bolt with part # FA74521 which might work for your application.
    view full answer...
  • V Mounting Brackets to Convert Conventional Trailer into Pontoon Boat Trailer
    The V mounting brackets that you could use to convert your conventional trailer to a pontoon boat trailer are the CE Smith V-Wing Bolster Bracket, # CE26244G. When it comes to mounting hardware for these brackets, I recommend using a screw and washer like our 3/8 Inch Stainless Steel Hex Lag Screw, # FA74521, and Stainless Steel Washer, # FA0152661. I have attached a link to our U-bolts for boat trailers. Since the mounting slot on the V bracket would typically run parallel with the...
    view full answer...
  • How Many V-Wing Brackets Are Needed To Support A 28-ft Long Pontoon Boat
    I contacted the manufacturer and one V-Wing Bolster Bracket, Item # CE26244G, should be placed at each frame cross member. Mounting hardware for these brackets is not included so I recommend using a screw and washer like our 3/8 Inch Stainless Steel Hex Lag Screw, Item # FA74521, and Stainless Steel Washer, Item # FA0152661. I have attached a video for you to check out.
    view full answer...
  • Recommended 5' Bunk Boards and Mounting Hardware For Boat Trailer
    We have just what you need. For the two 5' bunk boards I recommend the CE Smith Carpeted Bunk Boards for Boat Trailers - 5' Long - 1 Pair # CE27820, but the longest board we offer is 7' so for the two 109" boards you will need to get them from your local hardware store and use the CE Smith Deluxe Marine-Grade Carpeting for Bunk Boards - Black - 18' Long x 18" Wide # CE11349 to add the carpet to the boards. To secure the bunk boards to the bunk brackets Stainless Steel Hex Lag Screw -...
    view full answer...

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Info for this part was:

Employee Zack K
Video by:
Zack K
Employee Kathleen M
Installed by:
Kathleen M
Employee Randy B
Installed by:
Randy B

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