What is the difference between this Shimano BB-UN50 and the BB-UN55 ? The former is hard to find for sale, the latter seems to be found everywhere : r/bikewrench
Shimano シマノ ボトムブラケット BB-UN55 軸長118mm シェル幅68mm BSA スクエア 四角 /【Buyee】 "Buyee" Japanese Proxy Service | Buy from Japan! bot-online
Shimano BB UN55 bottom bracket BSA68 – 118mm – add-e – der E-Bike-Nachrüstsatz für Dein Fahrrad
Shimano UN55 Square Taper Bottom Bracket - BikePartners Bike Shop