The #8pro cup is an AC/DC polarity consumable with a 200 amp rating and has an inner diameter of .500 / 12.5mm. It is commonly used for most mild steel and stainless steel applications where good gas coverage is wanted and arc stability is critical. The #8 size cups are a great all around size for most industrial, Hot Rod and hobbyist applications. It will require 15-20 CFH of argon flow. You can run 3/32 (2.4 mm) or 1/16 (1.6 mm) tungsten with this cup. Please do not “walk the Cup” with any of the Furick cup line of Borosilicate glass cups.