From a 2001 ST2

Fits ST2 944 but I think it may be the same on some twin valve monsters and SS engines

43mm head 97mm long with 8mm shaft marked TRWT 80551/2

in good used condition 

I have been breaking Italian bikes for some time now so you will

find a lot more parts for Ducati 749,999 and 748, 916, 996 series bikes

in my  Ebay Shop .