SPLIT PINS CHAMPION

Split pins, also known as cotter pins, are metal fasteners with two tines that are bent during installation to secure components like nuts and axles. They are essential in mechanical applications to prevent parts from loosening due to vibration, and they are also widely used in crafts to create movable joints. 

Common Mechanical Uses
In engineering and automotive fields, split pins serve as critical safety components. 
Castellated Nuts: Secured by passing the pin through the slots (castellations) in the nut and a hole in the bolt to prevent rotation.
Clevis Pins: Used to lock a clevis pin in place after it has been inserted through a U-shaped fastener.
Axle Security: Frequently used to hold wheels on small axles or shafts.
Safety Fastening: Vital in high-vibration environments like aircraft control surfaces and marine engines to ensure fasteners remain seated. 

Creative and Craft Applications
In educational and hobbyist settings, split pins (often made of brass) are used to join lightweight materials. 

Movable Puppets: Used to attach limbs to paper or cardboard figures, allowing for jointed movement.
Educational Models: Helpful for demonstrating simple mechanisms like levers or creating working paper clocks.
Office & School: Commonly used as paper fasteners to bind documents or secure rotating wheels on learning charts. 

Materials and Durability
The choice of material depends on the environment and the required strength.
Zinc-Plated Steel: The most common and cost-effective option, providing basic corrosion resistance for indoor or general automotive use.
Stainless Steel (316/A4): Highly recommended for marine or coastal environments due to its superior resistance to salt-water corrosion.