This is a Master Lock System 29 padlock, which is somewhat special in that it can take a standard sized KIK lock cylinder. This enables you to change the cylinder to either match your house key, or to use a high security cylinder, as made by Assa, Medeco, etc. I'm including a cylinder with a 6-pin Kwikset keyway, with spools for pick resistance. It's ready to use as-is with the two included keys, or you can take it to a locksmith to have it repinned to match your hous...e key. The padlock is used, but in good condition. It's quite large - it measures 67mm wide, with a 11mm shackle. The shackle can not be shimmed open. I have other cylinders that I could install for an additional fee, if desired. Just send me a note.