Dual sided, shop quality bottom bracket tool for use with 12-notch or 36-notch external bottom brackets with an outside diameter of 48mm or 51.7mm respectively Compatible with Praxis M30 and M35 Compatible with any 3/8` driver External BB Socket 12/36-Notch 48mm/51.7mm BBT-35 Praxis 3/8`UPC/EAN/GTIN: 763477001146