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Pipes made before June 2011 carry a grade stamp of one digit and one letter. After that date grades were named using golf terms, rising in order: Teeing Ground (sandblasted and rustic), Fairway Blasted (smooth), Putting Green (sandblasted and smooth), Skins Game (special pipes from 2012 onward), and Hole in One (numbered collector pipes). The two-digit number next to the grade gives the year of production; the stamp 12 denotes 2012.