Odyssey mid bottom bracketthe most popular bottom bracket version in 2010 has to be the mid mid is basically a typical american size bearing without the aluminium collar since the twombolts use a 22mm spindle our mid bb is for a 22mm spindle if you have a mid bb frame and 19mm spindle you can get the american bb and just remove the aluminium collars buy odyssey components from chain reaction cycles the worlds largest online bike store