Chain Drive Sprocket 9T-60T Pitch 1/2″ 12.7mm For #40 08B Roller Chain A3 Steel
Material: A3 Steel. the Inner Hole of the Sprocket Is a Rough Hole with No Keyway and No Set Screw Hole. Rough Hole = Drilled Hole, No Precision (the Inner Hole May Vary Depending on the Batch).