Fits 2 Coupler Sizes: This coupler lock fits 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 Heavy-duty Anti-theft Design: Made from tough carbon steel, this trailer lock weighs 12.57 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 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 3 keys for your convenience Durable & Rust-resistant: The trailer hitch lock is powder-coated for corrosion resistance and features an aluminum alloy lock body for smooth use. A dust cap secures it from dampness, making it ready for any weather and extending its lifespan 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