High-strength Zinc Alloy Body With high safety, wear resistance and corrosion resistance, the high-strength metal code lock can be brand new and ensure safety even if it has been used for a long time. Hardened Steel Shackle The hardened steel shackle comes with a diameter of 7mm and has undergone multiple heat treatment to be harder, cut-proof, and safer. Stronger Lock Mechanism 12mm of the shackle is locked inside the lock body when in use, which is much longer and safer than most combination locker padlocks in the market. Hard to Decode The 4 digit combination lock provides 10,000 combinations with all wheels tightly fixed to make decoding nearly impossible. Easy to Set The code padlock allows setting your own code by simply flipping a "SET" switch at the bottom and back. Only four steps will do. Anti-Accidental Setting Protection Most combination locks can accidentally tamper with the code without knowing it like pocket dial, and will eventually become unusable. But this lock will not.