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-Aceƒâ€š ® 9000 series and XTRƒâ€š ® 980 series The other fits 16-notch bearing cups with an outside diameter of 48.5 mm such as FSA MegaEvoƒâ€š ® Made in the USA and covered by Park Tool's legendary limited lifetime warranty