This is the ultimate lock for use in marine or other outdoor environments where salt air is present and will cause corrosion. This is a 50mm padlock, and is 100% solid stainless steel, including inner parts like the cylinder and springs. This product is ideal for all types of boat docks, use on piers or anywhere the salt air corrodes traditional steel locks. As a global leader in security-related products and services, the BRINKS name is synonymous in top quality merchandise to keep you and your valuables safe. A credit to this tradition, our line of corrosion resistant locks are designed to perform in even the most harsh environments.