Secure Mindy Hardened Steel -Durable Padlock -AF4 70  is ideal for your home, office or house security.Ideal for medium to high risk of theft, the A&AF series Mindy padlocks are recommended for a wide range of security requirements. All models in this series have a paracentric keyway, zinc alloy plated cylinder cores and hardened steel shackle.Unique Lock core1.The key steps for 0.05mm;2.Leaf blade error 0.01mm;3.Locking plate and a locking groove clearance is 0.1mm;4.Spring leaves and the single type, as long as any side force can not be opened;5.Stainless steel lock, super anti violence on;6.The magic key to change and the error is 1, then automatic idle can not be opened.Hard to DuplicateThe padlock comes with 3 keys which is important as the keys are too unique to duplicate easily.Hard to be Cut OffThe lock is built to resists being picked by a shim (along the sides of the shackle), and also has a unique internal mechanism that is more difficult to pick. And, because there is a metal barrier that blocks the shackle, it is also more difficult to clip with bolt cutters.