... .stainless steel sprocket 4,OEM offer Sprocket for 12B-1 roller chain, The drawing is as followed, We can produce the ... ,JIS3) Processing: Forging-Machining-Hobbing4) Sprocket & Platwheel in European StandardNo. Stands Pitch Range 5MM,6MM,8MM,3/8" --> 3" 5) Type ...