Well, there are two answers, really..
You probably hit with a thing called a V-Core 98, or maybe a V-Core 89T even
However, Tomic doesn't use them anymore after his fairly disastrous 2012.
Tomic has gone back to his Head radicals I think..
5.0 all courter. 2 x Dunlop Bio 400T with cyclone @ 50, 1 x Dunlop Bio F400T gut @ 55
"Tennis isn't easy" - Corners