For example, Guardian makes
several o.e.m. windshields for Chrysler. They have the Safeguard logo,
but are labeled with Guardian's DOT #22. Throughout the years many
manufacturers have made auto glass for others. LOF and PPG has made
parts for Carlite, Viracon has made parts for LOF, and PPG makes parts
for Chrysler, just to name a few.
DOT (Dept. Of Transportation) code
numbers are assigned by NHTSA on request to automotive glazing
manufacturers in accordance with FMVSS No. 205, 'Glazing Materials.