Sunnyway 5/16" Trailer Coupler Wire Lock Pins — 10-Pack Gold, 4" Zinc-Plated Carbon Steel Heavy-Duty

Sunnyway 5/16" trailer coupler wire lock pins are heavy-duty, zinc-plated carbon steel pins, 4 inches long, sold in a 10-pack to secure trailer couplers, hitches, PTO shafts and other towing connections.

These Sunnyway pins replace shorter factory pins when you need extra reach and a robust locking solution for towing or equipment connections. Manufactured from carbon steel with a zinc finish, they resist corrosion better than raw steel and are sized to fit 5/16" coupler holes while offering a 4" overall length for added engagement and versatility. Each pack includes ten identical pins so you can outfit multiple trailers, spare assemblies, or service tools at once.

How will these pins improve trailer and hitch security?

The pins deliver a solid mechanical connection between trailer couplers and hitch receivers by fitting snugly through the coupler pin hole and locking in place. Their increased length gives more insertion depth than shorter pins, reducing side play and improving stability under load. The zinc plating adds a protective barrier against rust where steel is exposed to weather and road salts.

• 4" length increases engagement over standard 2-3/4" pins
• Zinc-plated carbon steel construction for strength and corrosion resistance
• Consistent 5/16" diameter for a secure fit in matching coupler holes

What dimensions and materials should I expect?

Each Sunnyway locking pin measures 4 inches end-to-end and is manufactured from high-strength carbon steel to withstand towing loads and repeated use. A zinc-plated finish covers the metal to reduce rust and surface wear. The 5/16" diameter suits a common coupler hole size; confirm your equipment’s pin size before ordering.

• Total length: 4 inches
• Pin diameter: 5/16 inch
• Material: carbon steel with zinc plating

How easy are these pins to install and remove in the field?

Sunnyway pins are designed for quick, tool-free installation: push the pin through aligned holes and secure it with the wire-lock mechanism. The wire-locking clip snaps into place and can be released by hand when you need to remove the pin. Their straightforward design makes them practical for frequent hookups, maintenance, and storage.

• Push-fit installation with hand-operated wire-lock clip
• Suitable for frequent assembly/disassembly tasks
• Uniform manufacturing tolerances for reliable, repeatable use

Where can I use these pins besides trailer couplers?

While ideal for trailers and hitches, these pins also work with agricultural implements, PTO shafts, gates, lawn equipment, and any setup that accepts a 5/16" locking pin. The extended length makes them useful where thicker collars or dual-plate connections need additional reach. Keep in mind correct diameter and load ratings for safety-critical applications.

• Trailer couplers and hitch assemblies
• PTO shafts, implements, and farm equipment
• Gates, tool carts, and other removable-pin connections

Who is this for? These Sunnyway 10-pack trailer coupler wire-lock pins are aimed at towing enthusiasts, small-fleet operators, landscapers, farmers, and DIYers who want a dependable, long-lasting pin that fits common 5/16" couplers and offers extra length. They suit anyone who needs multiple spare pins for service kits, backup hardware for trailers, or standardized pins across several pieces of equipment. Always verify compatibility with your coupler or assembly and follow manufacturer guidelines for safe towing and load management.