Trailer coupler. Cam-action lock. Rust-resistant zinc plating. Hitch Ball Size: 1-7/8", Class: I, Gross Trailer Weight: 2000 lb, Lock Type: Cam Lock, Finish: Zinc Plated No. 74042: Hitch Ball Size: 2", Class: II, Gross Trailer Weight: 3500 lb, Lock Type: Cam Lock, Finish: Zinc Plated