I oiled up the filter, and installed the stock plastic cage to try to screw it into the airbox and i tried for hours trying to screw in that filter but it would not go. It seems a little over sized for the 150r airboxes. But, ive had uni clamp on filters on my last 2 bikes and they were great. This one has great quality, but wont fit easily.
These filters were used to replace the filter box on an '89 Moto Guzzi Le Mans with two carburetors. The filters are top quality and they perform beautifully! The feature that really worked for me is that they are slightly flexible. That's important because space beside the left carburetor is limited and the filter needs to bend slightly inward from the bike frame in order to fit. The filter does that with no problem.