Tenacity Locks Ltd Installation guide (Watch till the very end): Do not weld locks onto steel doors or paint on the face of the lock (where the latch and bolt are). The heat from welding the locks greatly compromises the efficiency of some of the internal components of the lock. In as much as the lock might continue functioning after such welding, it's life time will be highly reduced. In some cases the lock will cease functioning properly immediately. RIVETING THE LOCKS PRODUCES BEST RESULTS AS