High-Quality Materials & Sturdy Construction The padlock is made of high-quality zinc alloy. The padlock shackle is made of stainless steel, resistant to rust and corrosion. It is the most durable and secure padlock. Super Security & Anti-Theft The 4-digit passwords provide 10,000 password combinations, which improves security and better protects your belongings. You can set any number combination you want as your password, but remember your password. There is a password window on the side to better protect the password wheel.