Innovative intake manifold in extreme heat and fuel-resistant FKM from the Malossi Racing MHR series. Rubber can be rotated in the aluminium base plate through 360° for ideal positioning. Intake manifold features 30mm opening and 35mm carb connection, making it ideal for 26-28mm PHBH and VHST carburetors. Perfect for maximum flow performance. Explanation: The difference between FPM, FKM, Viton® Behind the abbreviations or names mentioned is the identical basic material - fluororubber. FKM is the abbreviation for fluoroelastomers according to the American ASTM standard. Viton®, on the other hand, is a trademark of the company DuPont Performance Elastomers. In our range, all fluoro rubber articles are designated with the abbreviation FKM.