That's because it's Autobahn88 not Autobarn. Autobarn is the franchise retailer, Autobahn88 is the performance store that sells the copy Greddy plenums
On topic, my mate uses an Autobahn88 Greddy copy on his 25. Was decent quality, everything fitted together fine and the build quality was decent enough. For 400-500 odd bucks, can't go wrong.