2-5/16 Inch Trailer Hitch Coupler Lock – Anti-Theft Protection for RV, Boat, and Utility Trailers

Master Lock 378DAT Trailer Coupler Lock, 2-5/16-Inch

About this item

• Coupler lock is best used for trailers; Works best with Straight Tongue Trailer Couplers
• Advance locking mechanism resists picking and prying
• Designed to resist rust and corrosion
• Fits most couplers 1-7/8 in. (48 mm), 2 in. (51 mm) and 2-5/16 in. (59 mm); Does not fit Gooseneck Trailer Couplers
• Includes one trailer coupler lock, two keys

Protect your trailer, boat, camper, or utility equipment with this Heavy-Duty 2-5/16" Trailer Coupler Lock — a tough and reliable solution designed to keep your valuable cargo safe from theft. Built from solid, rust-resistant steel, this lock provides unmatched strength and durability for long-term outdoor use in any weather condition. Its universal design fits most standard 2-5/16-inch couplers, making it a must-have for anyone towing or storing trailers.

The high-security locking mechanism ensures maximum protection with a precision-engineered key cylinder that resists picking and tampering. Installation takes only a few seconds — simply place the lock on the coupler and turn the key to secure. Once locked, it creates a tight and secure fit that prevents unauthorized hitching or towing. Whether you’re parking your trailer overnight, storing your RV for the season, or leaving your boat at the marina, this coupler lock gives you peace of mind knowing your investment is protected.

Designed for performance, this trailer lock features a weatherproof finish that resists corrosion, dust, and road grime. The sturdy build can handle extreme heat, rain, or snow without rusting or seizing. Perfect for travel trailers, campers, boats, horse trailers, utility haulers, and cargo trailers, this lock adds an extra layer of defense against theft and damage.

With its compact size, rugged design, and easy operation, this 2-5/16" Trailer Coupler Lock is the ultimate choice for professional haulers, weekend adventurers, and anyone who values the security of their equipment. Protect your trailer with confidence and travel worry-free — this lock is built to last, built to secure, and built for peace of mind.

Brand New Open Box.