If you have ever removed your radiator from your FRS/BRZ you know how horrible the factory filler neck is, and if you have not removed your radiator, just take our word for it. Do yourself a favor and get yourself a CSF All Aluminum Filler Neck, you wont ever have to worry about your filler neck breaking or cracking. CSF has also included a 1.4 Bar high pressure radiator cap to give your whole cooling system a boost in performance. Make sure you do not get stuck during a radiator install or possibly on the road or track and upgrade your filler neck today.