This is a brand new 9 tooth front or rear miter box output sprocket for a Rokon 2 wheel drive motorcycle. It has both a 3/16″ wide keyway and a precision drilled 1/4″ diameter hole. The bore is 3/4 inch. The sprocket is supplied with a new roll pin, 2 set screws and a #606 Woodruff key. This sprocket is thin in the undercut area and was machined from a 5/8 inch bore sprocket because these are not available with a 3/4 inch bore. I do not recommend using this sprocket in a high power application with just a roll pin. It should hold up just fine as long as it is used on a woodruff key that is long enough to get under the tooth area. Do not use a set screw on top of the woodruff key.