The masterlock pro series shrouded shackle padlock range is designed to endure the toughest security applications by providing extra protection against corrosion abuse and attack they have tough boron alloy shackles dual ball bearing locking mechanisms for maximum pry resistance and layered laminated steel cores for strength the shrouded shackle design provides additional protection and the xenoy outer casing delivers excellent weather resilience the precision 6 pin cylinder delivers optimal pi