Grand Cru Sealed Bearing Jockey Wheels, 10 tooth
These are nice alloy 10-tooth jockey wheels. They comes with shims to fit many derailleurs. Modern derailleurs use 11-tooth wheels, so it's getting hard to find replacements for vintage derailleurs. The bearings are sealed for a long and smooth life. Through bolt diameter must be smaller than 5.1mm.
Price is for a pair of jockey wheels