Reliable Anti-theft Protection: This trailer coupler lock fits most trailers, RVs, and boats. Even if it feels loose, the anti-theft protection remains strong, ensuring your vehicle stays secure and protected, no matter where you park it Durable & Rust-resistant: The trailer hitch lock is powder-coated for corrosion resistance and features an all-copper lock cylinder for smooth use. A dust cap secures it from dampness, making it ready for any weather and extending its lifespan Quick & Easy Locking: Locking up takes less than 30 seconds! Simply unlock, place on the coupler, and secure. One-handed installation and an internal cushion pad ensure a tight, stable fit. Comes with 4 keys for your convenience Heavy-duty Anti-theft Design: Made from tough carbon steel, this trailer lock weighs 6.83 lbs with a 0.31-inch thick wall, resisting crowbars, drills, and tools. It’s built to keep your trailer secure and minimize the risk of theft Fits 3 Coupler Sizes: This coupler lock fits 1-7/8-inch (47.5 mm), 2-inch (50.6 mm), and 2-5/16-inch (58.6 mm) straight tongue ball couplers, offering security for your RV or trailer. Note: Check coupler size before purchase. Not for couplers wider than 4.34 in