Best U-Bolts of 2025

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U-Bolts are essential components in various industrial and scientific applications. These sturdy and durable fasteners are designed in a U-shape, making them ideal for securing pipes, rods, and other cylindrical objects. Made from high-quality materials such as stainless steel or galvanized steel, U-Bolts offer excellent resistance to corrosion and provide reliable support. With their versatile design, they are commonly used in construction, automotive, and plumbing industries. Whether you need to secure equipment or create a stable connection, U-Bolts are a reliable choice for any industrial or scientific project.
At a Glance: Our Top Picks
Top 10 U-Bolts
uxcell U-Bolts with Nuts and Washers
The uxcell U-Bolts Set includes four durable steel U-bolts with a 20mm inner width and a total length of 50mm. Each U-bolt features an M6 thread diameter, ensuring a secure fit for your projects. The set comes with hex nuts and round washers, making installation straightforward and efficient. With a galvanized finish, these U-bolts resist rust and corrosion, offering long-lasting performance. Ideal for fastening components to pipes or wood, this set is perfect for various applications, such as connecting boats, pipelines, and trailers.
Dunzy 4 pcs Zinc U Bolts
The Dunzy Zinc U Bolts come in a convenient pack of four, making them perfect for various fastening needs. Each U bolt measures 3/8 inch in diameter, 3 inches wide, and 7 inches long, which is ideal for securing 3 x 3 inch square objects. Made from sturdy carbon steel and coated with zinc, these bolts resist rust and corrosion, ensuring durability even in wet conditions. Additionally, the set includes frame plates and nuts, providing everything you need for installation. It's recommended to use lubricant during installation for easier handling and to prolong the life of the bolts.
uxcell 1.22" Round U-Bolts
The uxcell U-Bolts are designed with a 1.22-inch inner width and a total length of 90mm, making them perfect for various fastening needs. With an M8 thread diameter, these bolts fit securely onto rods measuring 31mm in size. The included hex nuts, sized at 14 x 6mm, ensure a tight grip when you need to secure components. Additionally, the galvanized steel construction provides excellent rust and corrosion resistance, extending the life of your projects. Whether you're working on boats, pipelines, or trailers, these durable U-bolts offer a reliable solution for your fastening tasks.
Therwen 16 Sets M6 U Bolts
The Therwen U Bolts Set is a complete fastening solution for your projects. It comes with 16 U bolts, plates, nuts, and washers, so you can start working right away without needing to buy extra parts. Each U bolt is sized conveniently at 1.57 inches wide and 3.54 inches long, making them versatile for various applications. Made of galvanized steel, these bolts resist rust and corrosion, ensuring durability over time. Whether you're a DIY enthusiast or a contractor, you’ll appreciate the reliability and security this set offers for fastening materials like wood and pipes.
National Hardware Square U Bolt #535
The National Hardware U Bolt is a reliable solution for securing items to both wood and metal surfaces. Made from durable stainless steel, it ensures long-lasting use whether you apply it indoors or outdoors. The included nuts make installation a breeze, allowing you to set everything up quickly and efficiently. If you need additional support, you can easily pair this U bolt with National's compatible plates for enhanced stability. This versatility makes it a great choice for various projects around your home or workshop.
Prime-Line U-Bolts
Introducing the Prime-Line U-Bolts, the perfect solution for securing pipes, conduits, cables, or other cylindrical objects. These U-bolts are made from high-quality zinc-plated steel, ensuring durability and corrosion resistance. With a diameter-thread size of 5/16 inch-18 and an inside width compatible with 1-inch pipes, these U-bolts are versatile and can be used for various applications. They come with a U-bolt plate and two nuts for easy installation. The coarse thread type and blunt point style make them suitable for a wide range of projects. Whether you're a DIY enthusiast or a professional, the Prime-Line U-Bolts offer convenience, reliability, and peace of mind.
National Hardware U Bolt N222-562
The National Hardware U Bolt is a versatile fastening solution, perfect for securing items to pipes, wood, and more. Its durable steel wire construction ensures that it can withstand both interior and exterior conditions, making it suitable for a variety of applications, including automotive and plumbing needs. With the included plate and nuts, you can enjoy hassle-free installation, saving you time and effort. This U Bolt provides a reliable way to keep your projects secure, giving you peace of mind whether you’re working at home or in an industrial setting.
Stainless Steel Square U-Bolt with Nuts and Plate
Get the job done quickly with the 304 Stainless Steel Square U-Bolt. This rust-resistant and durable U-bolt comes with additional accessories, including 8 hexagon nuts and 4 plates, all galvanized for extra protection. The U-bolt has a good grip and performs well in harsh weather conditions, making it suitable for automobiles, trailers, boats, and other industrial applications. With a size of 2" W x 4.3 L" and a thread length of 2 inches, it is perfect for 2" x 2" square beams and shafts.
Homaisson 4 Pcs Square U Bolts
The Homaisson Square U Bolts come with four robust U bolts, frame plates, and hex nuts, providing everything you need for your fastening tasks. Made from high-quality stainless steel, these bolts offer incredible strength, making them ideal for heavy-duty applications without worrying about deformation or rust. Their dimensions are perfect for fitting 3x3" square objects, ensuring versatility for various projects. Additionally, the user-friendly design allows for a secure installation, enhanced by the included hardware. You’ll appreciate the convenience of using these U bolts for all your fastening needs.
National Hardware N222-455 2193BC U Bolt in Stainless Steel
The National Hardware U Bolt is a versatile fastening product designed for a variety of applications. Whether you need to secure something to a pipe, wood, or other surfaces, this U Bolt is up to the task. It is suitable for automotive, plumbing, and other home and industrial uses, making it a handy tool to have around. The plate and nuts are included, saving you time and effort in finding compatible accessories. Made from stainless steel, this U Bolt is not only durable but also resistant to corrosion, making it excellent for marine and outdoor applications. With the National Hardware U Bolt, you can trust that your fastening needs are well taken care of.
Frequently Asked Questions (FAQs)
1. What is a U-bolt used for?
A U-bolt is a type of industrial fastener that has a U shape with two threaded arms extending from a curved base. It is commonly used to support pipework or attach parts to poles, beams, or walls. The U shape provides stability and keeps the bolt firmly in place, adding support to the structure.
2. How do you specify a U-bolt?
To specify a U-bolt for pipes, you need to provide the diameter of the pipe, the material, the tangent length, and either the load or thickness of the U-bolt rod. These specifications ensure that the U-bolt is the correct size and strength for the intended application.
3. Which is better Grade 5 or Grade 8 bolts?
Grade 8 bolts are stronger than Grade 5 bolts as they have undergone a more extensive hardening process. Grade 8 bolts are typically used in demanding applications, such as automotive suspensions, where high strength is required. However, the choice between Grade 5 and Grade 8 bolts depends on the specific needs of the application.
During our u-bolt research, we found 24 u-bolt products and shortlisted 10 quality products. We collected and analyzed 6,686 customer reviews through our big data system to write the u-bolts list. We found that most customers choose u-bolts with an average price of $19.21.
The u-bolts are available for purchase. We have researched hundreds of brands and picked the top brands of u-bolts, including uxcell, Dunzy, Therwen, National Hardware, CDOKY. The seller of top 1 product has received honest feedback from 18,493 consumers with an average rating of 4.8.

Brian Howie is a content writer and senior industrial designer. After graduation from Westminster College, he has been engaged in product design and manufacturing for 18 years. Brian Howie has always found great pleasure in designing industrial products and sharing his ideas and experience online.