Every print that ever crossed my bench had a stamp on it somewhere. FINAL. ENGINEERING ISSUE. Somebody's initials in a circle telling you the job had been checked and it was good to go. Red ink, blue ink, green, black, whatever pad happened to be sitting open on the foreman's desk that day. I made these four to look like they came off that same desk. My own Tool and Die Guy seal, Erie, Pennsylvania, stamped once in each of the four colors every shop office kept in the drawer. Masonite hardboard with a cork back, 3.75 by 3.75 inches, made to sit under a hot coffee on your bench and take it.