Pre-pro shot glasses come in various different shapes and sizes and they also also come with different types of label.    

The most common method of branding a glass was with a white "frosted" label.  It was used on more than 85% of all pre-pro glasses.  It's often described by online auction sellers as being "acid etched" because that's how it appears, but this type of label was actually created by stamping on a labeling compound and then firing it onto the glass. This type of label wears off through repeated use and eventually fades to the point where a mere ghost of the original remains.

'Old Barton Pure Rye'  from R. S. Strader & Sons, Lexington, KY	'Overbrook Rye Whiskey', a brand registered by Albert Blum, NY, but the monogram suggests a different issuer	'Old Mission Wine Co.', from Indianapolis, IN