The Trimax UMAX25D Dual-Purpose Coupler Lock acts as a universal coupler lock as well as a universal U-lock, providing 360° of solid steel protection against trailer theft. The UMAX25D is constructed of solid hardened steel and a die-cast body. It fits most coupler sizes from 1-7/8" to 2-5/16". A 1/2" fully hardened steel shackle helps ensure your trailer is secure, even when left unattended. It has a patented dual locking system and a rust-proof epoxy finish for extra security.• Patented dual purpose coupler lock and U-lock• Dual-ratchet locking system• Fits most couplers (1-7/8", 2", 2-5/16")• Rugged corrosion-resistant epoxy finish• 1/2" hardened steel shackle Constructed of solid hardened steel and a die-cast body Fits most coupler sizes from 1-7/8" to 2-5/16" 1/2" fully hardened steel shackle helps ensure your trailer is secure | UMAX25D Dual Coupler Lock with Integrated U-Lock