china din 8187 industry sprocket 12a22t 3 china din 8187 industry sprocket 12a22t 3 1. produce strictly in accordance with ansi or din standard dimension 2. material c45 steel / stainless steel 304 & 316 3. standard ansi, din, jins, iso, standard america or customer drawing 4. pilot bore, finished bore, taper bore and special bore. 5. bright