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Grade 5 Steel or Stronger
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Square bend 3/8 inch U-bolt rod, made in the USA with precision and durability. These square U-bolts are available in various lengths and inside diameters, feature a fine thread, are non-coated and are made of grade 5 steel. Specifically designed for secure fastening in automotive, farm, trailer, construction and marine applications. Enhance your project's performance with the reliability of our professionally crafted U-bolt rods.
3/8 Inch Square U-Bolt Details:
- U-Bolt made in the USA.
- U-bolts are sold individually.
- Plates sold separately.
- U-bolts are made to order and may be up to 1" longer per leg than ordered length.
- Torque Specification: 26 FT LBS.
- Grade: SAE grade 5 steel
- U-Bolt Material: Raw steel (non-coated)
- Thread Direction: Right-hand thread
- Thread Type: Standard NF fine thread
- Size And Threads Per Inch: 3/8-24
Overall rating: 4.8 / 5 from 422 reviews.
You guys did a great job of building these u bolts for me! I used them to mount a piece of square tubing to the frame of my travel trailer so I could have a place to store my weight distribution hitch when not in use! Thank you, Angelo, and all the folks that helped me out. And also for the fast delivery!
I had to bolt a utility box to a trailer frame. Your company had the exact size I needed.
Perfect product!
They four perfect.
I’m modifying an implement toolbar and was looking for some ubolts. No one local had what I wanted. Searched online and found this site, easily selected the right size I wanted and placed the order. They shipped quick and I had them in hand quickly. They work as expected. If I need ubolts in the future I’m trying these guys right away.
It was exactly as I ordered it and fit as I had planned! 10/10
Good quality - perfect fit
Great quick service and value
U-bolts were a perfect fit for mounting spare trailer tires on my utility trailer and boat trailer. Couldn’t find 10 inch long by 4 inch wide u-bolts locally. I’ll keep you in mind for future projects, thanks for the fast delivery.
Holding together my motorcycle carrier. Now very sturdy compared to original design.
I got longer u-bolts so I could double nut using hi-nuts. The size was perfect and there was no rattling on my towbar. The supplied anti rattle u-bolt was only long enough for a washer and locknut which would loosen up after 10-20 miles. Didn’t want to use high strength loctite because I occasionally remove the hitch riser. These u-bolts solved my problem and I received them quickly. Thanks for the great product and great service
Excellent service and quick delivery! Perfect!
Original trailer step bolts broke easily. Ordered these from U-bolt Store and got high quality material with a perfect fit.
Bolts are exactly as specifications states. Sized perfectly. Quick delivery
Good quality bolts and arrived at a good time
Perfect fit
U-bolts fit nicely, used on boat trailer, adjusted quickly to get boat hight level
I made my own ladder hold-down by cutting one end of the u-bolt off 1¼ inch from the bottom to make a J-bolt. That catches the roof rack cross bar and the other end goes through another cross bar that sits on top of the ladder. Works great!
not square like was suppose to be ordered
The bolts were perfect once I read the proper way to measure a u-bolt on your website, I needed them to attach a plate over the existing springs for an air bag application, and the shipping is unbelievably fast and the prices are great, if and when I need u-bolts The U-bolt Store will be the place I will get them from. Thanks again for the fast efficient services Daron F.
It fits as expected.
Excellent quality!! Clean threads. Nuts cover many threads for excellent bolt purchase and holding ability
I had to trim off the ends, but expected this... not a problem They fit well and are inplace working just fine. Thank you.
I couldn’t figure out a way to secure a 4x4 post to a corner chainlink fence post. There is a tree right next to it the post, so digging a hole was out of the question. Then it dawned on me. Why not use 4in square u bolts with plates. Well it worked out perfect! Couldn’t be happier with the way it came out. An the U bolts are strong and sturdy.
Needed to replace u-bolts after rebuilding boat trailer. U-bolts worked perfectly and they look good too!
Very satisfied Products exactly as described Fit perfectly
What I ordered is what I got. It worked for me and was exactly what I wanted.
I needed a special fastener for a handrail project. The custom made U-Bolt from you folks worked perfectly
I needed custom bolts to secure cargo boxes to a custom 6x6 steel rv bumper. These fit exactly to order. Thank you.
I perused your inventory. I ordered my needed item. I got it! It worked! It was not overpriced. I was satisfied . Done deal!!
U-bolts worked great going to add a RV door to side of my trailer and added the I beam under the frame to help support the opening. thanks!!! I will definitely be back!!!!
Great experience with ordering and receiving item. I really appreciated the educational aspect of the website with regards to proper measurements. Thanks
Other than the Chinese junk that’s found at the local hardware store, UBolts is just the right size are tough to find. I even searched McMaster-Carr to no avail. At first, I ordered UBolts that were too short, so I ordered ones that were two inches longer and trimmed them down as needed. I have a four-post car lift and needed to mount a winch to the horizontal cross member. Pushing a heavy, non-running car up the ramps and onto the lift is no picnic! The UBolts, nuts and washers all appear to be of great quality and just what I needed. Shipping fees seems a bit higher than one should expect, so be aware of that when you order. I spent as much for shipping as the items on the order itself. All-in-all, I am satisfied with the outcome and prompt service from UBolt Store.
Hard to find size at a good price. Shipping was more than the product. I forgot to order nuts and being fine thread a little more difficult to get locally.
Great service excellent quality precise engineering
I am working on a 1974 boat trailer. All of the square u bolts needed to be replaced as most were cut off. Your business is the only one I found that has, or will make them to a specific size. The ones I purchased fit perfectly. Will buy again when I needed.
3/8 Inch Diameter U-Bolts - Square
Store owner replied: Great to hear Olen! Thank you!
Just what I need to replace my old ubolts and pretty quick delivery
Its great...thanks for the prompt delivery..
We misunderstood how the bolts were measured, so we ordered them 1 inch to short. Not to happy that we can't exchange them for what we actually need. But, we should have read better. Had to re-order a longer length.
Arrived safe and quickly. Great quality. Definitely found my place for quality ubolts at a great price.
