5/16″ D x 3″ L Coupler Locking Pin Aftermarket (751011-1) by Sea Dog. Square Coupler Pins add an additional level of security, preventing accidental uncoupling while in transit to better protect your trailer. The snap lock bale is spring tensioned for stronger holding power. Fits most coupler sizes. Constructed of electro-galvanized steel for corrosion resistance.

• Ideal to make trailer towing safer and easier
• Made from the highest-quality materials to last for years to come
• Guaranteed to meet the highest standards of quality and durability
• Designed to withstand the toughest abuse