The Park Tool  BBT-29 Bottom Bracket Tool is a double-ended bottom bracket wrench designed to fit 16-notch bearing cups with an outside diameter of 39mm (e.g. Shimano® Dura-Ace® 9000 series and XTR® 980 series) as well as 16-notch bearing cups with an outside diameter of 48.5mm (e.g. FSA® MegaEvo®).   Park Tool  BBT-29 Bottom Bracket Tool Features  The BBT-29 is a double-ended bottom bracket wrench designed to fit non-standard diameter 16-notch external bottom bracket bearing cups One end fits cups with an outside diameter of 39 mm such as Shimano Dura-Ace® 9000 series and XTR® 980 series The other fits 16-notch bearing cups with an outside diameter of 48.5 mm such as FSA MegaEvo® Made in the USA and covered by Park Tool's legendary limited lifetime warranty