need very quick help

[99gsx]

plz go to this website and see if u can help me: http://www.hksusa.com/categories/more.asp?id=1092

wat is GT25 Inlet Flange?
Wa is GT30 outlet flange?

 

[rubbersidedown]

i think the type of flange it has tells you the type of exhaust manifold its made to bolt to.