Tacx jockey wheels are amongst the best in the market key features the very smooth running jockey wheels by tacx are manufactured from a resin composite that is very resistant to wear and equipped with quality precision bearings thanks to the closed bearings they will not get stuck show play or squeak high grade precision stainless sealed cartridge bearings colour grey upper and lower jockey wheels provided for use with campagnolo 8 9 and 10 speed shimano 7 and 8 speed