Phenolic Spacer: Simple and effective product. The phenolic spacer is made of high-temp phenolic plastic that isolates the MAF\throttlebody from the supercharger. This keeps the MAF\throttlebody cooler and still allows for coolant to flow between the supercharger and throttlebody. By keeping the throttlebody cool it will won't heat up the incoming air to the supercharger, making for better performance. The spacer is $79.99 including gaskets and is available from Ram Air Technology. This is not a worth while upgrade in my opinion but I put it here as a option to you. It is very helpful if you are looking to run water injection or NOS. Rather then tap into the metal on the supercharger you can tap into this spacer. NOS or water running through your throttlebody sensors is not a good idea and will eventually lead to failure, always install after the throttlebody\MAF.