Product Description
This is a quality aftermarket 40 series driver and driven pulleys.
Driver has a 1″ bore with 1/4″ key.
Driven is 7 5/8″ diameter with 5/8, or 3/4″ bore and 3/16″ key way.
Refer to the Comet 40 series belt chart to choose the correct belt.
https://www.gopowersports.com/Comet/40seriesBELTS.htm
40 series uses a 7/8″ wide belt, this setup is rated up to 18hp.

This is an inboard mount driven unit, if outboard mount is needed please specify in the comment section.
Quality aftermarket, not made by Comet