Master Lock 389DAT Trailer Coupler Lock — Universal Fit for 1-7/8 in, 2 in, and 2-5/16 in

Your versatile trailer security solution

Protect your trailer with the Master Lock 389DAT universal trailer coupler lock. It is designed to fit most common hitch sizes: 1-7/8 in (48 mm), 2 in (51 mm), and 2-5/16 in (59 mm) couplers, offering flexibility across different trailers and hitch setups. The compact form makes storage easy when not in use, while the locking core delivers dependable security during trips, storage, or site visits.

The bright red finish isn’t just bold styling—it helps make the lock more visible, acting as a deterrent in busy parking lots, campsites, or job sites. With a focus on practicality, the lock is built for straightforward installation and removal, so you can secure your trailer quickly when you’re on the go.

• Universal compatibility with common coupler sizes
• Bright red finish that enhances visibility and acts as a deterrent
• Advanced locking mechanism resists picking and prying
• Rust and corrosion resistance for varied environments
• Easy installation and removal for fast use on the go
• Limited Lifetime Warranty for ongoing peace of mind

In real-world use, you might secure a bike trailer after a weekend ride, lock a builder’s trailer at a job site, or leave a hitch attached while you run errands. While no lock guarantees security, the 389DAT is designed to provide credible deterrence through sturdy construction and a trusted brand.

Key features at a glance

• Universal fit for 1-7/8", 2", and 2-5/16" couplers
• Deterrent bright red finish for enhanced visibility
• Advanced locking core resists picking and prying
• Rust and corrosion resistance for diverse conditions
• Easy installation and quick removal
• Limited Lifetime Warranty

Real-world scenarios include securing a bike trailer after a weekend ride, protecting equipment trailers at a job site, or leaving a hitch attached while you run errands — with the idea that deterrence comes from solid construction and a trusted brand you can rely on. Maintenance is simple: wipe away moisture, inspect for signs of wear, and ensure smooth operation of the locking mechanism. This model is designed to offer practical daily security for trailer owners seeking a credible, brand-backed option.

Getting the most from your Master Lock 389DAT

• Store the key in a safe place and check fit before long trips
• Use on compatible couplers to prevent over-tightening
• Regularly inspect for corrosion and exercise the lock periodically
• Keep warranty information handy for quick service if needed