This is a used Yale padlock and chain with a new Abloy Disklock Pro cylinder and four new keys.  The keyway is restricted so no additional keys can be made; this gives you key control.  If you give a key to someone and then get the key back, you will know for sure the person has not made a copy.  This is a high security padlock; it has a Underwriters Laboratory rating, as evidenced by the "UL" on the face of the cylinder, which means that the cylinder has passed its requirements for security and pick resistance.  It also means that it has drill resistance.  Please look at my other items because I'll combine shipping whenever possible if the purchases are made within one hour.  This will be a private listing because photos of the keys have been shown.  Search words:  Medeco, Schlage Primus, Kaba, Bilock, Vachette, Assa, Anchor Las.