Best Square Nuts of 2026

Brian Howie Avatar
Brian Howie
Last Updated: Jan 8, 2026

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Square nuts are a type of fastener that possess a unique shape, featuring four equal sides and a threaded hole in the center. These nuts are designed to be used with bolts or threaded rods, providing a secure and tight connection. With their square shape, they offer increased surface contact and resistance to rotation, making them ideal for applications where loosening or vibrations are a concern. Square nuts are commonly used in construction, automotive, and machinery industries, offering durability and reliability in various settings.

At a Glance: Our Top Picks

Hillman 3334 Zinc Plated Square Nuts 10-24, 60-Pack Cover #TOP 1
Hillman 3334 Zinc Plated Square Nuts 10-24, 60-Pack
ftb score rating icon 9.9
The Hillman Group 160298 Square Nut Cover #TOP 2
The Hillman Group 160298 Square Nut
ftb score rating icon 9.8
uxcell M6 Square Nuts Kit Cover #TOP 3
uxcell M6 Square Nuts Kit
ftb score rating icon 9.6

Top 10 Square Nuts

#TOP 1

Hillman 3334 Zinc Plated Square Nuts 10-24, 60-Pack

3334
Silver
#10-24
Hillman 3334 Zinc Plated Square Nuts 10-24, 60-Pack Cover
The Hillman Group 3334 10-24 Square Nut Zinc Plated, 60-Pack

The Hillman Zinc Square Nuts are designed with a classic square shape, making them ideal for pairing with square-headed bolts. This design ensures a secure fit, which is helpful if you’re working on projects that require strong fastening. These nuts also serve well as blind nuts in furniture making, offering a neat and sturdy finish. They come zinc-plated, which means they resist rust and corrosion moderately, so you can trust them to last longer in various environments. With 60 nuts in each pack, you’ll have plenty on hand for your tasks without frequent reordering.

What We Like
Square shape for secure fit
Suitable for furniture use
Zinc plating for corrosion resistance
Large 60-pack quantity
#TOP 2

The Hillman Group 160298 Square Nut

160298
Silver
#10-32, 2.31 inches
The Hillman Group 160298 Square Nut Cover
The Hillman Group 160298 1 1 1 10-32 Square Nut, 100-Pack

The Hillman Square Nut is designed to work seamlessly with square-headed bolts. Its unique shape helps distribute the load evenly, enhancing the strength of your fastener. When used alongside flat washers, these nuts prevent damage caused by sharp edges, ensuring a secure fit and increased durability. The zinc-plated finish offers moderate corrosion resistance, making it suitable for various applications. This means you can rely on these nuts in environments where moisture may be a concern, providing you with peace of mind in your projects.

What We Like
Square shape for better load distribution
Prevents damage from sharp edges
Zinc-plated for corrosion resistance
Durable and reliable in various environments
#TOP 3

uxcell M6 Square Nuts Kit

a20112100ux0110
White
M6x20mmx5mm
uxcell M6 Square Nuts Kit Cover
uxcell Square Nuts, M6x20mmx5mm Zinc-Plated Metric Coarse Thread Assortment Kit, 10 Pcs

The uxcell Square Nuts are designed with a threaded size of M6 x 1mm, making them versatile for various applications. With a width of 0.78 inches and a height of 0.2 inches, these nuts fit perfectly with standard screws, providing secure connections. Constructed from carbon steel and finished with a white zinc coating, they resist rust and corrosion, ensuring durability in both indoor and outdoor settings. You can easily tighten them using a wrench, making installation straightforward and hassle-free for your projects.

What We Like
Durable carbon steel construction
Rust and corrosion resistant
Easy to install with tools
Versatile for multiple applications
#TOP 4

The Hillman Group 3342 Square Nut

3342
Silver
3/4"-10
The Hillman Group 3342 Square Nut Cover
The Hillman Group 3342 3/4-10 Square Nut Zinc Plated, 5-Pack

The Hillman Square Nut is designed to fit perfectly with square-headed bolts, making it an essential component for various projects. Its square shape ensures a secure grip, providing stability in your applications. Additionally, these nuts can serve as blind nuts in furniture manufacturing, allowing for clean and hidden fastening solutions. With a zinc plating, they offer moderate protection against corrosion, ensuring durability over time. Each pack contains five nuts, giving you enough supply for multiple uses or repairs.

What We Like
Secure fit with square bolts
Ideal for furniture assembly
Corrosion-resistant zinc plating
Convenient 5-pack quantity
#TOP 5

M3nS A2 Stainless Steel Thin Square Nuts for PRUSA & Zaribo 3D Printers

Generic
M3nS
Silver
M3nS A2 Stainless Steel Thin Square Nuts for PRUSA & Zaribo 3D Printers Cover
M3nS - Thin M3 Square Nuts for PRUSA & Zaribo 3D Printers - A2 Stainless Steel - Conform to DIN 562 (Quantity 25)

The Generic M3nS Square Nuts are designed to perfectly fit your PRUSA 3D printer and compatible OEM parts, ensuring a hassle-free replacement or upgrade. Made from durable A2 stainless steel, these nuts resist rust and corrosion, so you can trust they’ll last with proper care. They simplify your DIY projects by making assembly of PRUSA or Zaribo components straightforward and easy. Manufactured to precise DIN 562 standards, their exact size and thread pitch guarantee smooth installation and reliable performance. These nuts are a practical choice for anyone working on 3D printer maintenance or customization.

What We Like
Perfect fit for PRUSA parts
Rust-resistant stainless steel
Easy DIY assembly
Precise DIN 562 sizing
#TOP 6

Hard-to-Find Fastener Coarse Square Nuts

014973314552
silver
1/2-13-Inch
Hard-to-Find Fastener Coarse Square Nuts Cover
Hard-to-Find Fastener 014973314552 Coarse Square Nuts, 1/2-13, Piece-10

The Hard-to-Find Fastener Coarse Square Nuts are a versatile and reliable option for your fastening needs. With a diameter of 1/2", these square nuts are made of high-quality steel and feature a zinc finish, ensuring durability and corrosion resistance. The 13 (coarse) thread type provides a strong grip, making it easy to secure your materials. The square nut design allows for greater torque and prevents the nut from rotating, offering stability and security. Whether you're working on a DIY project or a professional construction job, these square nuts will provide the convenience and peace of mind you need.

What We Like
Versatile
Durable
Strong grip
#TOP 7

Hillman 3336 Zinc Plated Square Nuts 1/4-20, 40-Pack

3336
Silver
1/4"
Hillman 3336 Zinc Plated Square Nuts 1/4-20, 40-Pack Cover
Hillman 3336 1/4-20 Square Nut Zinc Plated, 40-Pack

The Hillman Square Nuts 40-Pack offers you durable square-shaped nuts designed to fit square-headed bolts, making assembly straightforward and secure. They can also be used as blind nuts, which is especially handy if you're working on furniture projects and need hidden fasteners. These nuts come zinc-plated, providing a layer of protection against rust and corrosion, so they last longer even in moderate moisture conditions. With 40 pieces in a pack, you get plenty of nuts for multiple projects, giving you convenience and value in one set.

What We Like
Square shape for secure fit
Blind nut use in furniture
Zinc plating for rust resistance
Large quantity pack
#TOP 8

Hard-to-Find Fastener Coarse Square Nuts 3/4-10 Pack of 5

014973314576
Silver
3/4-10-Inch
Hard-to-Find Fastener Coarse Square Nuts 3/4-10 Pack of 5 Cover
Hard-to-Find Fastener 014973314576 Coarse Square Nuts, 3/4-10, Piece-5

The Hard-to-Find Fastener Square Nuts are designed with a 3/4-inch diameter, making them suitable for various fastening needs where a sturdy hold is required. With a thickness close to 21/32 inches, these nuts provide a solid grip that helps keep your projects secure. Made from durable steel, they offer strength and long-lasting performance, so you don’t have to worry about wear and tear. The zinc finish adds a layer of protection against rust and corrosion, ensuring these nuts stay in good condition even in challenging environments. The 1-1/8 inch wrench driver size makes installation straightforward and convenient for you.

What We Like
Durable steel material
Rust-resistant zinc finish
Sturdy 3/4-inch diameter
Easy wrench driver size
Solid 21/32-inch thickness
#TOP 9

uxcell M4-0.7x2.2 Carbon Steel Square Nuts 50pcs

f24032100ux0191
light brown
M4-0.7x2.2mm
uxcell M4-0.7x2.2 Carbon Steel Square Nuts 50pcs Cover
uxcell M4-0.7x2.2 Square Nuts, Carbon Steel Zinc Plated Coarse Thread Square Nuts Fasteners for Home Repairs and Professional Engineering, Colorful 50pcs

The uxcell M4 Square Nuts come in a pack of 50, each measuring 4mm in diameter and 2mm thick, making them easy to match with the right screws for your projects. Made from durable carbon steel, these nuts resist corrosion and handle heat well, so they last longer even in tough conditions. Their simple square design with beveled edges and coarse threads ensures a secure fit, preventing slipping and keeping bolts firmly in place. Installation is straightforward—just align the screws with pre-drilled holes, insert the nuts, and tighten them for a reliable hold. These nuts offer convenience and strength for both DIY enthusiasts and professionals.

What We Like
Durable carbon steel
Secure coarse threads
Easy installation
Compact size and quantity
#TOP 10

uxcell M5-0.8x4 304 Stainless Steel Square Nuts

f24032100ux0562
Silver
M5-0.8x4mm
uxcell M5-0.8x4 304 Stainless Steel Square Nuts Cover
uxcell M5-0.8x4 Square Nuts, 304 Stainless Steel Coarse Thread Square Nuts Fasteners for Home Repairs and Professional Engineering, Silver, 10pcs

The uxcell Stainless Steel Nuts come in a pack of 10, each measuring M5-0.8x4 with precise dimensions that make them easy to fit into your projects. Made from durable 304 stainless steel, these nuts resist corrosion and heat, ensuring they last through tough conditions. Their simple square shape with beveled edges pairs perfectly with screws, offering a secure lock that prevents slipping. Installing them is straightforward: just match the right screws, insert, and tighten. This convenience makes these nuts ideal for both home repairs and professional tasks where reliability matters.

What We Like
Durable stainless steel
Secure locking design
Easy installation
Precise dimensions
Buying Guide Image

Frequently Asked Questions (FAQs)

1. Why did we stop using square nuts?

Square nuts were commonly used on machinery in the past, but they required more space to tighten. Hexagonal bolts and nuts became popular in the early 19th century due to their more compact design and ease of use.

2. What is the disadvantage of square nut?

One disadvantage of using square nuts is that they may not fit properly in some applications where the fastener hole is not precisely square. Additionally, square nuts can be more challenging to tighten or loosen compared to hex nuts, as they may require a special tool or wrench to hold the square shape while turning.

3. What is the purpose of a square nut?

Square nuts are commonly used in applications where there is an inset or channel in the receiving surface, such as in furniture, railroad applications, or other metal assemblies. The larger surface area of square nuts allows them to resist loosening more effectively.

Editor's Notes

During our square nut research, we found 24 square nut products and shortlisted 10 quality products. We collected and analyzed 6,045 customer reviews through our big data system to write the square nuts list. We found that most customers choose square nuts with an average price of $7.62.

The square nuts are available for purchase. We have researched hundreds of brands and picked the top brands of square nuts, including Hillman, uxcell, Hard-to-Find Fastener. The seller of top 1 product has received honest feedback from 384 consumers with an average rating of 4.7.

Written by
Brian Howie Avatar

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.