PACLOCK's UCS-2A is an all-purpose padlock that's machined from 6061 aircraft-grade aluminum. It features an industry-first 5/16" diameter "hardened stainless steel" shackle that is tough to cut and weather resistant. All brass, aluminum, and stainless steel components render the lock rustproof. All brass, aluminum, and stainless steel components render the lock rustproof. Our 6-Pin technology (more than the industry standard 4 pins) provides over 20,000 unique key codes and makes duplicate key combinations extremely rare, meaning that your key number is virtually unique to you. The stainless steel spool and serrated security pins make the lock pick, bump, and drill resistant. Includes the PAC-BAND, a field-replaceable silicone cover to protect the cylinder from the elements. CNC machined for precision and reliability, the lock body exceeds +/-0.003” tolerances for repeatable quality. There is no other retail product on the market today that solves customers padlock keying problems like PACLOCK's Universal Cylinder System (UCS). UCS provides YOU with maximum flexibility over YOUR key system with its “Every Lock, One Key” mentality. Key different-styled UCS padlocks alike, such as job box locks, trailer door locks, and coupler locks, just to name a few. YOU become your own locksmith and get to change your keying since UCS makes it easy for you to pin up your own cylinders at any given time. Whether your locking system gets compromised and you need to quickly change up your keying system, or you just fired an employee who still has a key to your locks, or you have keyed different padlocks but want to key them alike – UCS makes key changing simple. You can also quickly change your shackles to transform your locks from a standard length shackle to a longer length shackle, or vice versa, at any time.