Pins are manufactured and stocked in a variety of styles, materials, and lengths. Some of the more common styles include clevis, cotter, cotterless, dowel, roll/spring, groove, hitch, tapered, coiled, hairpin, and adjustable and are briefly discussed below.

Clevis pins are cylindrical fasteners commonly used in mechanical linkages to connect two components, enabling a pivotal connection with the help of a U-shaped clevis. The pin passes through the holes in the clevis and the parts to be connected, facilitating controlled motion and rotation. Clevis pins are crucial for creating versatile and easily adjustable connections in applications such as automotive linkages, agricultural equipment, machinery, and various industrial settings. Secured in place by a cotter pin or similar retainer, clevis pins offer simplicity, reliability, and versatility in establishing movable connections between components, making them integral in diverse mechanical systems where articulation and rotation are essential. 

Cotter pins, also known as split pins, or cotter keys in the US, are metal fasteners with two tines bent during installation.They serve as a reliable locking mechanism to prevent nuts, bolts, clevis pins, and other fasteners from unintentionally loosening or disengaging. They are inserted through corresponding holes in fasteners and secured by bending their tines in opposite directions, providing a visible and secure locking solution. Their simplicity, ease of installation, and reusability make cotter pins a popular choice for safety-critical scenarios where preventing the accidental disassembly of components is crucial. Cotter pins are typically made of thick wire with a half-circular cross section, and come in different materials, and multiple types and sizes. Common materials include: mild steel, brass, bronze phosphor, stainless steel, and copper. These fasteners meet several aerospace and industrial strandards such as LN 94, SP 90, L 23310, EN 2028, EN 2367 or ISO 1234, BS 1574, and DIN 94 respectively. Widely used in automotive, aviation, construction, and machinery applications, cotter pins are versatile and easy to visually inspect. Cotterless pins, also known as a quick-release or detent pins, are tool-free fastening devices designed for easy assembly and disassembly. Featuring a cylindrical body with a spring-loaded detent mechanism, these pins allow for rapid insertion and removal without the need for additional tools. Cotterless pins come in various configurations, including straight, T-handle, and button-handle designs, and find widespread use in machinery, manufacturing, and equipment assembly where frequent adjustments or swift connections are essential. They are available in different materials and sizes to suit various applications, providing a convenient and efficient alternative to traditional cotter pins.

Dowel pins are cylindrical fasteners used to precisely align and join components in various applications such as woodworking and machinery assembly. By inserting dowel pins into corresponding holes in mating parts, these pins ensure accurate positioning, prevent relative movement, and enhance the structural integrity of the assembly. Dowel pins streamline the assembly process by simplifying alignment and contribute to stability. They come in different sizes and materials, featuring various end types to suit specific application requirements. While effective for many purposes, dowel pins may be used in conjunction with other fasteners in high-stress situations for a more robust connection.

A roll spring pin, also known as a tension pin, is a hollow cylindrical fastener designed for aligning and joining components in mechanical assemblies. Constructed with a split down its length, the pin exerts outward radial force upon insertion into corresponding holes, ensuring a secure fit and alignment. Roll spring pins excel at transferring both tension and shear loads between connected parts, distributing forces evenly and resisting stress concentration. Their ease of installation and removal, coupled with vibration resistance, makes them a cost-effective choice for various applications, particularly in automotive, machinery, and manufacturing industries. The pin's spring-like action provides flexibility and reliability, contributing to its widespread use in scenarios where movement and vibrations are common.

A groove pin is also a cylindrical fastener featuring grooves or channels along its length, designed for ease of assembly and disassembly. Constructed from materials like steel or stainless steel, groove pins are utilized to join and align components in various applications, including machinery, automotive, and industrial settings. Their flexibility allows for simplified insertion and removal, making them advantageous in scenarios requiring frequent adjustments or maintenance. Groove pins contribute to precise alignment, effective load distribution between connected components, and securing rotating elements like pulleys and gears. Available in different sizes and configurations, groove pins offer versatility to meet specific load-bearing requirements and environmental conditions within diverse assemblies.

Hitch pins are removable fasteners commonly used for securing trailer hitches to vehicles, as well as attaching agricultural implements to tractors. The design typically includes a straight pin with a handle or knob on one end and a clip or cotter pin on the other end. Hitch pins facilitate quick and temporary connections by passing through pre-drilled holes in the components, allowing for easy attachment and removal. Widely recognized for their versatility, hitch pins are employed in recreational, agricultural, and industrial settings where frequent coupling and decoupling are necessary. Their straightforward design and efficient functionality make them a practical choice for applications requiring a reliable yet easily adjustable connection between towed equipment and towing vehicles.

A tapered (taper) pin, is a conically shaped fastener designed for securing and aligning components in mechanical assemblies. Featuring a gradual increase in diameter along its length, tapered pins are commonly used in dowel and shaft connections, ensuring a tight fit that prevents relative movement between connected parts. Their ease of installation and removal makes them suitable for applications where precision and simplicity are vital, allowing for straightforward insertion into corresponding tapered holes. Widely employed in manufacturing, automotive, and machinery industries, tapered pins provide reliable and easily adjustable connections, contributing to the stability and accuracy of assemblies. The selection of the appropriate size and material is crucial, taking into account factors such as load-bearing capacity, environmental conditions, and the required level of precision in the assembly.

Coiled or spring pins are flexible fasteners crafted from coiled spring steel wire. Designed for creating secure and resilient connections between components. Widely used in machinery, automotive, and industrial applications, coiled pins are inserted into matching holes where they exert outward radial force, establishing a tight and stable fit. Their unique design allows them to absorb shocks and vibrations, making them suitable for dynamic scenarios. Coiled pins prevent relative movement between connected components, enhancing the overall stability and integrity of the assembly. With a relatively simple installation process and versatility in applications requiring a combination of strength, flexibility, and shock absorption, coiled pins provide a reliable solution in various industrial settings.

Hairpins, also known as a hairpin cotters or hairpin clips, are U-shaped pins commonly used in various industries such as automotive and machinery manufacturing. With one end featuring an open loop and the other splitting into two straight prongs, hairpin fasteners are designed for securing components by passing the open loop through a designated hole or slot and hooking the prongs around another part. Their ease of assembly and disassembly, without the need for additional tools, makes them ideal for applications requiring frequent adjustments or maintenance. Hairpin fasteners provide a quick and secure connection, preventing unintended disengagement and contributing to the efficiency of assemblies. They are versatile, available in different sizes and materials, and are chosen for their simplicity and effectiveness in creating semi-permanent or temporary connections.

Adjustable pin fasteners come in various forms, such as clevis pins with threaded holes or quick-release pins with adjustable locking mechanisms, offering flexibility in adjusting the length of the pin. These fasteners are commonly utilized in industries like machinery, automotive, and manufacturing where precise adjustments or quick disassembly are essential. Clevis pins with threaded holes allow for alterations in length using a threaded fastener, while quick-release pins with adjustable locking mechanisms provide easy customization. These versatile pins are employed to fine-tune connections, accommodate variations in assembly, or facilitate swift changes in configurations. Available in different materials and designs to meet specific requirements, adjustable pin fasteners provide a convenient and adaptable solution for applications demanding flexibility in assembly and disassembly processes.