The master lock excell stainless steel discus padlocks are made with cutting edge technology to deliver unprecedented security they feature tough cut patented octagonal boron carbide shackles which are 50 tougher to cut than hardened steel offering optimum weather resistance with the additional security of a shrouded shackle which is much tougher to pullpry open they have a precision 4 pin cylinder and are supplied with a lifetime warranty against mechanical failure supplied with 4 keys and a l