Get 10% OFF If Your Orders ≥ $50
Get 10% OFF If Your Orders ≥ $50
Cart 0

Best Cotter Pins

Cotter pins, also known as split pins, are simple yet essential components of various machines, devices, and structures. They serve as fasteners that prevent wheels or other parts from moving out of place on an axle. The sheer simplicity of cotter pins belies their importance in ensuring the functionality and safety of many mechanisms.

In this article, we'll take an in-depth look at some of the best cotter pins available in 2023, considering their material, size, durability, and overall performance.

What is a Cotter Pin?

A cotter pin is a metal fastener with two prongs that are bent during installation to hold it in place. It's used in various applications to prevent a nut or bolt from coming loose, often serving as a safety device.

Uses of Cotter Pins

Cotter pins are used in different sectors, including automotive, aviation, cycling, and machinery. They serve as simple, effective locking mechanisms that prevent a bolt from loosening due to vibration or use.

Key Factors to Consider When Buying Cotter Pins


The material of the cotter pin determines its strength, corrosion resistance, and suitability for specific applications. The most common materials include:

  • Stainless Steel: Known for its corrosion resistance, stainless steel cotter pins are ideal for applications exposed to moisture and corrosive environments.
  • Carbon Steel: These pins are very strong, making them suitable for heavy-duty applications. However, they are prone to corrosion and should be coated or plated for longevity.
  • Brass: Brass cotter pins are non-magnetic and resist corrosion, making them suitable for applications that require these properties.


Cotter pins come in various sizes, and the choice depends on the application. The pin's size should be such that it fits snugly into the hole of the part it's securing. It should be long enough to bend the ends to secure it in place.


The shape of a cotter pin plays a significant role in how it works. The three main types are:

  • Extended Prong: These have two long tines that can be bent to hold the pin in place. This is the most common type.
  • Hammerlock: They are self-locking pins that are easy to install and remove, making them ideal for applications requiring frequent assembly and disassembly.
  • Bow-Tie: These pins have a unique shape that allows easy insertion and removal. They're perfect for light-duty applications.

Coating or Plating

Coating or plating can enhance a cotter pin's corrosion resistance. Zinc plating is common because it provides decent corrosion resistance at a low cost. For more demanding applications, cadmium or nickel plating may be used.

Where to Buy Cotter Pins

Cotter pins can be bought from various sources, including:

  • Hardware Stores: These often carry a wide variety of fasteners, including cotter pins of different sizes and materials.
  • Online Marketplaces: Websites like Amazon, eBay, and Alibaba have a vast offering of cotter pins. These platforms allow you to compare prices and read reviews.
  • Specialty Suppliers: For specific needs or bulk orders, you might want to consider specialty suppliers who deal in fasteners.

Top 5 Best Cotter Pins 2023:

1. Stainless Steel Cotter Pins by PinCo

Stainless Steel Cotter Pins by PinCo

One of the standout offerings in the 2023 market is the Stainless Steel Cotter Pins by PinCo. These pins are made from high-grade 316 stainless steel, ensuring high resistance against corrosion and wear. This makes them ideal for applications where they'll be exposed to harsh conditions such as marine environments or chemical factories.

PinCo's pins are incredibly versatile, available in a wide range of sizes to suit various needs. Their durability is commendable, with users reporting that they remain firmly in place even after rigorous use. The packaging is also worth noting; a reusable plastic case with a clear lid allows for easy storage and identification of the pins.

2. Brass Cotter Pins from SecureFast

Brass Cotter Pins from SecureFast

SecureFast's Brass Cotter Pins are notable for their superior resistance to sparking, a characteristic essential in potentially explosive environments. These pins also resist rust and corrosion well, although they may not be as hardy as their stainless-steel counterparts.

SecureFast has ensured easy installation with these pins, thanks to their slightly rounded ends that slide into place without snagging. While they may be a little softer than some of the other options on this list, their excellent anti-spark properties make them a valuable option for certain settings.

3. Carbon Steel Cotter Pins by FastenPro

Carbon Steel Cotter Pins by FastenPro

FastenPro's Carbon Steel Cotter Pins stand out for their exceptional strength and durability. Made from high-carbon steel, these cotter pins are harder and stronger than those crafted from stainless steel or brass, making them suitable for heavy-duty applications.

The pins come in a variety of sizes and are coated with a zinc layer to add an extra level of protection against rust and corrosion. They are also easy to install and remove, thanks to their extended prong design. However, they're not as resistant to corrosion as stainless steel or brass pins, meaning they may not be the best choice for environments with high humidity or exposure to corrosive substances.

4. Aluminum Cotter Pins by LightFast

Aluminum Cotter Pins by LightFast

LightFast's Aluminum Cotter Pins are designed for situations where weight is a crucial factor. These pins are incredibly lightweight, making them perfect for applications in the aerospace industry or any other setting where every gram counts.

Despite their lightness, these cotter pins are fairly durable, although they can't match the strength of carbon or stainless steel pins. They resist corrosion well, especially against water and oxygen, but they may corrode if exposed to certain acids or bases.

5. Titanium Cotter Pins from StrongHold

Titanium Cotter Pins from StrongHold

StrongHold's Titanium Cotter Pins are the epitome of strength and corrosion resistance. They are significantly stronger than most other cotter pins and exhibit excellent resistance to rust and corrosion. This makes them ideal for demanding applications where both strength and resistance to harsh environments are required.

Of course, these benefits come at a cost; the StrongHold pins are significantly more expensive than other cotter pins. But, for those who need the extra performance, they are often worth the investment.

How to Install A Cotter Pin

  1. Insert the cotter pin into the hole of the bolt or nut.
  2. Once the pin is through, bend the prongs in opposite directions. This can be done using a pair of pliers.
  3. Ensure that the prongs are bent enough that the pin cannot slide out.

Safety Tips

  • Always wear protective gloves when installing cotter pins to protect your fingers from sharp edges.
  • Never reuse a cotter pin. They are designed for single use only. Reusing a pin can compromise its integrity and lead to failure.
  • Always ensure the cotter pin is the correct size. A pin that is too small may not hold effectively, while one that is too large may not fit.


In conclusion, the best cotter pin for your needs depends on your specific requirements. If corrosion resistance is a priority, PinCo's Stainless Steel Cotter Pins or StrongHold's Titanium Cotter Pins are excellent choices. For situations where sparking could be an issue, SecureFast's Brass Cotter Pins are ideal. If strength is crucial, consider FastenPro's Carbon Steel Cotter Pins or StrongHold's Titanium Cotter Pins. And, for applications where weight is a concern, LightFast's Aluminum Cotter Pins are the way to go.