Career Union Journeyman Glazier here. L.O.F. = Libby, Owens, Ford. Read left to right, obviously. "HI-TEST SAFETY PLATE" A.S.-W.S. "auto-safety, windshield safety" I have forgotten what the LY was abbreviated for. Perhaps late 1960's to mid 1970's glass. Unfortunately, there is not a date stamp so more than likely not original glass. These days, Laminated glass for automotive use is "AS-2". This code means that the Poly-Vinyl Laminate sheet is 45 thousandths of an inch thick as opposed to "AS-1" which is for commercial bldg. and trades use at 25 thou.