sprockets and chains 1,ANSI all type 2,high precision cnc tech ... machinery, metallurgy, mine, build, electron, port etc..professional automation production and conveying transmission equipment MaterialC45, A3, 40Cr, 20CrMnTi, 42CrMo, copper, ... stainless steel and so on as per your requestprocessForged or castingHeat treatmentHigh frequency ...