BB-UN55 vs BB-UN300 - which is the better square taper bottom bracket? - restoration.bike
Shimano Bottom Bracket Parts BB-UN55 BC 1.37 x 24 | eBay
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 UN55 68 x 113mm Square Taper English Bottom Bracket | Green Mountain Bikes
FAQLoad - Shimano BB-UN55 bottom bracket
Shimano BB-UN55 MTB Road Bike Square Taper Bottom Bracket 68mm - AliExpress Sports & Entertainment