Master Lock Trailer Receiver Lock 1479DAT 5/8in Barbell™ Push-to-Lock — Weather-Resistant, 10,000 lb Rated

The Master Lock 1479DAT is a 5/8in (16mm) Barbell™ receiver lock that secures 5/8in trailer receiver pins with a push-to-lock action and weather-resistant protection.

Built to fit standard 5/8in (16mm) trailer receiver pins, the 1479DAT combines a simple push-to-lock operation with corrosion-resistant features and a high load rating for heavy-duty towing applications. The lock accepts a usable receiver pin length of 2-3/4in (70mm) and uses a 4-pin cylinder for improved pick resistance. A Weather Tough seal and water-tight cap help keep moisture and debris out of the locking mechanism, and Master Lock backs the product with a limited lifetime warranty for long-term ownership confidence.

How does the push-to-lock feature speed hitching and unhitching?

The push-to-lock design removes the need to turn a key while securing the receiver. Simply slide the lock body onto the exposed pin, press firmly until it engages, and remove the key—locking is complete in seconds. This saves time during hitching and helps ensure the lock is correctly seated before towing.

• One-handed operation for quick installation
• No key rotation required to lock
• Key only used to unlock, reducing fumbling at the hitch

Will it withstand outdoor exposure and road conditions?

The 1479DAT was designed with outdoor use in mind: a Weather Tough seal and a water-tight cap protect the cylinder and internal components from moisture, dirt, and road grime. While no lock is indestructible, these measures help maintain smooth operation and reduce corrosion over time. Routine inspection and basic care will maximize longevity in variable climates.

• Weather Tough seal resists water intrusion
• Water-tight cap shields the keyway from debris
• Sturdy metal construction suited for trailer use

How secure is the lock against theft and tampering?

The 4-pin cylinder increases resistance to common picking techniques compared with simpler mechanisms, and the Barbell™ design clamps over the receiver pin to prevent easy removal. The lock carries a Class III/IV 10,000 lb load rating, indicating its suitability for heavy trailer use rather than serving as an absolute theft-proof device. Combining this lock with good hitching practices and additional security measures improves overall protection.

• 4-pin cylinder for added pick resistance
• Barbell design locks over the receiver pin securely
• Class III/IV 10,000 lb load rating for heavy-duty applications

What size receivers and pin lengths does it fit?

This model fits standard 5/8in (16mm) trailer receivers and accommodates a usable receiver pin length of 2-3/4in (70mm). Verify your trailer’s pin dimensions before purchase to ensure compatibility. If your receiver or pin falls outside these measurements, consider a different model tailored to that size.

• Fits 5/8in (16mm) receiver openings
• Usable pin length: 2-3/4in (70mm)
• K1 key blank for replacement key reference

Who is this for? The Master Lock 1479DAT is intended for trailer owners, landscapers, contractors, and anyone who regularly tows with a 5/8in receiver and wants a fast, durable locking solution with weather-resistant protection. It’s especially useful for those who value a quick push-to-lock operation, need a lock rated for heavy towing loads, and prefer a product from a recognized security brand.