Bicycle Cassette & FreewheelChina Shimano Bicycle Parts 7 Speed Freewheel Tz500-7 14-28t 14-34t (same as TZ21) Bike Flywheel, Find details about China Bicycle Freewheel, Shimano Tz500-7 from Shimano Bicycle Parts 7 Speed Freewheel Tz500-7 14-28t 14-34t (same as TZ21) Bike Flywheel