An unexpected rough section on your ride? No problem with this rim. Looking for a bomb-proof rim to build up your Gravel, Cyclocross, or adventure bike? Then it's definitely worth taking a look at the RR 521 rim. 32mm deep and 20mm wide, this modern road rim could have been classified as a Cross Country rim just a few years ago. Nowadays it's just a great offer to widen your ride... with drop bars.