BB cups for Shimano compact
 

I recently bought a used FC-R700 compact crankset and along with it came a the bottom bracket unit that is labeled as SM-FC4500, which is a Tiagra level Hollowtech, I think. Will this work? What is the difference between the tiagra level and the ultegra level bb cups? (When i bought the crank i assumed i was getting the ultegra bb so that is another issue i'll have to take up with the seller). I read online at places that sell the R700 that the 6600 Ultegra level bb is "required" Thanks for any help.

I'm using an Ultegra BB with a Tiagra compact. It works fine, should work your way.