BlackStar H40A45 - 40 Pitch A-Plate Sprocket - 45 ToothThe BlackStar H40A45 is a 40 pitch A Plate roller chain sprocket with 45 teeth, precision manufactured from SAE 1045 steel with induction hardened teeth for extended wear life and features machine cut tooth profiles for smooth, reliable chain engagement. Specifications Part Number H40A45 Chain Pitch 40 Number of Teeth 45 Bore Type Plain Bore Hub Style A Plate Strand Count Single Material Steel Hardened Teeth Yes Outside Diameter 7. 45" Pitch Diameter