Idler Sprocket Bore Diameter 1 in Number of Teeth 18 Outside Diameter 3.1 in Pitch 0.5 in Compatible Tightener Shaft Grainger Part Number 813Y51 Bearing Type Needle Roller Compatible Tightener Shaft Manufacturer Part Number N2 Face Width 3 in For Belt Series H For Belt Trade Size H For Belt Width 3 in Material Fabrication Cast Number of Flanges 2