Chain Sprocket Bore Diameter 1/4 in For Chain Pitch 1/4 in For Number of Strands Single Hub Type One Side Material Stainless Steel Maximum Bore Diameter 7/8 in Number of Teeth 20 Outside Diameter 1.728 in Pitch Diameter 1.598 in Bore Type Plain Chain Number 25 Finish Plain Hub Diameter 1 1/4 in Hub Projection 0.625 in Standards REACH Certification RoHS Compliant