... .Good anticorrosive capability 3.Long life 4.Competitive price SPA/B/C belt pulley,1. Feature MaterialCast iron,steel, plastic,ect.ProcessingSan ... 3 grooves A type: 4 grooves B type: 1 grooves B type:3 to 5 grooves B type: 6 grooves C type: 2 ... .It used for transmission as followed, 8.Contact details, SPA/B/C belt pulley