2004 outback exhaust question

i have a friend with the 2004 outback h4 cali emissions and has the exhaust that looks exactly like an h6 exhaust. 3 cats and 5 sensors single oval ports on the heads. is the h6 exhaust the same thing or is there something different about it that it wont fit? the h6 cats can be found cheaper than the ones that say there for the h4 specifically.

You will need to check the VIN and see if the car was the 50 state car or a cali car emisisons. The 50 state cars have different emissions and controls than the cali cars.

 

more information here

 

https://www.subaruoutback.org/threads/2004-h4-california-emissions-outback.525689/

it is a cali car has single port exhaust drive by wire says h4 on the airbox 2 af sensors 3o2 sensors 3 cats.