Originally Posted by HillRider

All Shimano freehubs that take a 9-speed cassette will also take an 8-speed or a 10-speed cassette. No extra spacers are needed for the 8-speed. You would need a 4.5 mm spacer to fit a 7-speed cassette and a 1 mm spacer (it comes with the cassettes) to use a 10-speed cassette.