This spacer is necessary if you need to fit an 8-10sp cassette onto an 11sp hub. You will need appropriate tools to remove and refit the cassette, such as a chain whip, cassette lockring tool, and a large wrench.
3mm Aluminium Cassette Spacer - 7 Speed Cassette on 8/9 Body, Fits Shimano
VGEBY Bicycle Spacer, Ultra-Light Aluminum Alloy Cassette Spacer for 8-Speed 7-Speed Road Bike Bottom Bracket Gasket Black for Cyclists Mechanics Touring Commuting Racing Maintenance
Aluminum Alloy Cassette Spacer for 8 9 10 11 Speed Freewheel, 1.8mm Hub Gasket Shim for Road Mountain For Bike Freehub Adjustment, Silver(2mm Black)
GENUINE SHIMANO 1.0mm CASSETTE SPACER FOR DURA ACE, ULTEGRA & 105
SHIMANO FH9000 1.85mm 10 speed CASSETTE SPACER FOR 11 speed FREEHUB BODY
Yosoo Health Gear Bike Cassette Spacer, 3 Pcs Aluminium Alloy Flywheel Hub Spacer 1mm+1.5mm+2mm Bicycle Freewheel Washer Cassette Bracket Axle Hub Spacer for Mountain Bike, Road Bike
