exhaust gasket?

[pinky]

Hey guys i just got my rnr 3inch exhaust, my question is simple, the gasket between the o2 and the exhaust is much smaller than 3inch...do i use the old one or do i have to buy a 3 inch gasket...the 02 is much smaller than 3inch....someone help me out here...am i missing something?

 

[gritsak]

just use a gasket that matches up with the size of your o2 housing.