Double-Pitch Sprocket, S Roller Type / R Roller Type

S Roller Type: For use with double-pitch chains for small conveyors. Sprockets with 21 teeth or fewer are made of carbon steel for machine structural use with induction-hardened tooth tips.
Those with 22 teeth or more are made of normal steel (SS400) with weld-on hubs.
R Roller Type: For use with double-pitch chains for small conveyors.
Sprockets with a low number of teeth are made of carbon steel for machine structural use (not hardened).
Sprockets with a high number of teeth are made of normal steel (SS400) with weld-on hubs.