Trailer Coupler Lock, Heavy-Duty 2-5/16 in, 3 Keys

Trailer coupler lock helps deter theft by securing a 2-5/16 in (58.6 mm) flanged air flow coupler with a heavy-duty, close-fitting steel shell. Built for RV, boat, and trailer parking, it shields the coupler from prying and tampering while staying easy to use. Powder-coated carbon steel resists corrosion, and the included keys make lockup and access straightforward.

• Fits 2-5/16 in (58.6 mm) flanged air flow couplers; check coupler size before purchase.


• Delivers heavy-duty protection with thick-wall carbon steel to resist prying, drilling, and common tools.


• Installs in under 30 seconds; unlock, place over coupler, and lock—easy one-handed operation.


• Includes 3 keys plus an internal cushion pad for a tighter, more stable fit on the coupler.


• Resists rust with powder coating, a smooth aluminum-alloy lock body, and a dust cap to help block moisture.

When your trailer is left in a driveway, storage lot, campground, or marina, the coupler is a common target. This anti-theft trailer tongue lock covers the coupler to reduce access to latch and hardware, adding a visible layer of protection without slowing you down at hookup time. Designed for wide use across trailers, RVs, and boats, it’s a practical upgrade for frequent travelers and long-term parking alike. Grab yours today and lock up with confidence.

• Compatible coupler size: 2-5/16 in / 58.6 mm


• Coupler type: Flanged air flow coupler


• Main material: Carbon steel with surface coating


• Lock body material: Aluminum alloy


• Product weight: 10.36 lb / 4.7 kg


• Wall thickness: 0.24 in / 6 mm


• Outer dimensions: Ø5.59 x 6.89 in (Ø142 x 175 mm)


• Internal diameter: 5.04 in / 128 mm


• Internal depth: 4.92 in / 125 mm


• Keys: 3