KC's LKZ Light Lock accessory line provides peace of mind to consumers wary of potential theft of their lighting investment. With our 100% CNC machined steel construction and anti-corrosive Zinc coat KC light locks are designed to last keeping your light investment safe for many years to come.100% CNC Machined Steel ConstructionClear Zinc Coat Plated Finish for long-lasting Corrosion ProtectionDiameter Thread Size: M12-1.75mmKit Includes (2) M12-1.75 specific Security Nuts and (1) Key Each Tube Clamp Mount comes complete with rubber shims for a fine tune fitment of lights securely attaching your lights with a range of adjustability for your lighting needs. Forget rust-prone steel KC HiLiTES has constructed.