I installed a Eurocode HFC a little over a week ago. I popped a P0420 code (second O2 out of tolerance) fairly quickly (not unexpected). I know that once I push software it would go away but it would still show up as Emissions not ready if scanned. Decided to give RAI spacer a shot. I ordered over the weekend. Monday, I got the shipped notification which was nice. I'm not far away but was surprised to have it on my doorstep Tuesday evening (UPS ground). Excellent build quality. I installed it and cleared my CEL, I have only gotten one shakedown drive to try and set the CEL again. I wish it had came with a guide to what orifice to install for different applications. If it helps I went no orifice installed. If this fails then I will record the O2 voltage reading and work my way down the sizes.