Sea-Dog Coupler Pin 751010-1, 1/4 Inch Square Trailer Coupler Locking Pin, Electro-Galvanized Steel

The Sea-Dog 751010-1 is a square coupler locking pin built to secure your trailer coupler and prevent accidental uncoupling while in transit. Constructed of electro-galvanized steel, it resists corrosion from road spray, launch ramps, and general outdoor exposure, making it well suited to boat trailers and other towed equipment stored near water. The pin uses a snap lock bale that is spring tensioned, giving it stronger holding power than a simple friction-fit pin so it stays seated over rough roads and repeated hitching cycles.

Sized at 1/4 inch, the 751010-1 is designed to fit most coupler sizes, making it a straightforward upgrade or replacement for a worn, bent, or missing coupler pin. It ships as a single pin and is a simple, tool-free installation: insert the pin through the coupler latch and snap the spring-loaded bale closed to lock it in place. Because it is sold individually, it is easy to keep a spare on hand or to replace just the one pin that has failed rather than an entire coupler lock assembly.

Specifications

• Brand: Sea-Dog
• Manufacturer Part Number: 751010-1
• Material: Electro-Galvanized Steel
• Pin Diameter (A): 1/4 inch
• Overall Length (B): 3 inches
• Dimension C: 1-13/16 inches
• Dimension D: 7/16 inch
• Dimension E: 13/16 inch
• Weight: 0.106 pounds
• UPC: 035514751025
• GTIN: 00035514751025
• Standard Pack: 10 each
• Coupler Fitment: Fits most coupler sizes

Fitment

Fits most trailer coupler sizes at the 1/4 inch pin size; no specific make, model, or year fitment is specified.

Replaces (OEM)

No OEM cross-reference numbers are specified for this part.

Frequently Asked Questions

What size is the Sea-Dog 751010-1 coupler pin? The Sea-Dog 751010-1 is a 1/4 inch square coupler locking pin, with an overall length of 3 inches.

What is the 751010-1 pin made of? It is made of electro-galvanized steel, which provides corrosion resistance for outdoor and marine trailer use.

Will this pin fit my trailer coupler? The 751010-1 is designed to fit most coupler sizes at the 1/4 inch pin diameter; check your coupler's latch opening against the 1/4 inch pin size before ordering.

How does the locking mechanism work? A spring-tensioned snap lock bale holds the 751010-1 pin in place once inserted, giving it stronger holding power than a plain friction pin and helping prevent accidental uncoupling in transit.

How many pins come in a package? The Sea-Dog 751010-1 is sold as a single coupler pin, one piece per unit.

How much does the 751010-1 weigh? The pin weighs 0.106 pounds.

Is installation tool-free? Yes, installation is tool-free: insert the pin through the coupler latch and snap the spring-loaded bale closed to lock it.

Is there a larger size available? Sea-Dog offers a related coupler pin, part number 751011-1, at 5/16 inch, which is a separate SKU from the 1/4 inch 751010-1 pin.

What is the UPC for this part? The UPC for the Sea-Dog 751010-1 coupler pin is 035514751025.

Does this pin resist rust? Yes, the electro-galvanized steel construction of the 751010-1 is built to resist corrosion in wet and outdoor trailering conditions.

What does dimension C, D, and E refer to on this pin? For the 751010-1, dimension C measures 1-13/16 inches, dimension D measures 7/16 inch, and dimension E measures 13/16 inch, describing the pin's additional body and bale dimensions.

Can I use this pin as a replacement for a lost or broken coupler pin? Yes, the 751010-1 is intended as a direct replacement coupler pin for coupler locks that use a 1/4 inch square pin.