Campagnolo Xenon Rear Derailleur

This is a 9/10 speed rear derailleur in which the dimensions of the cage have been slightly modified to interface with the 10v chain, which is narrower than the 9v one.
The short cage Upper to lower pulley-axledimension is 55mm, while the medium cage is 72.5mm.
Weight 253g for short cage and 258g for medium cage.