Review on Red CNC Air Fuel Mixture Screw: Adjustable Carburetor FCR Air Screw for KEIHIN Carbs on 4-Stroke Motocross Motorcycles by Matt Louis

I gave this product only one star. The reason is that this is the second air/fuel mixture screw I've bought from Revain and it doesn't fit the WR450F as stated in the description. The spring is too big and the bottom gasket doesn't fit into the carburetor, so the screw doesn't catch on the threads in the carburetor! I have started by returning the first screw sent to me and will not do it again for this purchase without wasting time and money again so I will consider it a loss and order from another supplier!