The locks we supply here are for use in cabinets, glass cases, lockers and the like. It's easy enough to find a Yale or Chubb for a door but these are the ones for staff lockers or display cases or cupboards that need a little security. Locks can be supplied in key alike or key different versions, some with a master key. The 900 will give up to 1 million key changes. Push locks can be opened or locked by pushing the cylinder.