Polished Smooth Air Cleaner OTAC4SCPolished Smooth Air Cleaner4" O. D X 3 5 8" H Suit 2 5 8" Carburettor Neck OTAC4SC AC4SC This O'Brien Truckers original has deep traditional fins that allow you to paint it to match your engine colour and add an extra zing to your engine compartment. They come with a subtle grey coloured lifetime cotton gauze washable element contained in a never rust wire mesh. No cheap paper element here!