Markus,

I've got the same fitted to my 95 WRX and you need to replace the Green Foam filter inside.

I got mine from Nitosport, around £20 I think and it was delivered in record time. Great service Nito..

OM

 

I have a 'green mushroom' HKS induction kit on the blackbeast. The filter is getting rather grubby so I'd like a new one.

So, what exactly is it called (super/mega power flow filter?)

where is the best/cheapest place to get one? pref online supplier, or mail order.

 

Got my first replacement from NITO as well, but emailed him and he said he does not have any in stock at the moment

 

just ordered one from