Measurements: 48 inches wide x 12 inches tall
 
There are two holes on the top for mounting, the sign has a maker's mark of 'Property of Goodyear Tire & Rubber Company' and also DAS 1983.  The maker's marks are on both sides.
 
This is a painted metal sign and there are some paint flaws and minor wear consistent with age in our opinion.  Take a look and let us know if you have any questions.