Ducati Generator Part No: 264.4.017.1A
It will fit the 999, s & R 749 & S, 1098, S, Tricolour, R upto 2010
you can check the part number agianst your bike here:
http://www.ducati.com/services/maintenance/index.do It seems Ducati also use a denso unit.
I bought it because I thought mine was broken. However on closer inspection, found it was the wiring between this and the rectifier.....fortunately.
Had it checked by a Ducati dealer, they verified it is reconditioned.
Paid about 80 for it. On fleebay for £80, discount to DSC of £15.