Quote Originally Posted by safeman View Post
Mark, the safe code prefix AH refers to a manufacture date of 1902 and I attach a copy of the relevant leaflet.
Click image for larger version.  Name: Milner List 2.JPG  Views: 18  Size: 162.9 KB  ID: 19750The body thickness will be 3/16ths of an inch (4.764 mm). The door plate will be ⅜" thickened to ⅝" at the edges by 2¼"x 2¼"x ¼" angle forming lockcase. There will be a ⅜" ply-steel drill-resisting plate over the lock area.
Thank you very much for all the help you have given me with my Safes it is very much appreciated. You are a mine of very useful and interesting information. Thanks again.