Swirl Flap Delete Kit for BMW 6 Cylinder M57N / M57N2 Engines 22mm x 6!!! FREE POSTAGE !!! Swirl Flap Delete Kit for BMW 6 Cylinder M57N M57N2 Engines There is 2 sizes in the M57, please check with ones you have before ordering. There are the 22mm, the other size is 33mm This kit removes the problematic swirl flaps that are known to degrade and eventually disintegrate. This then ends up being sucked into the engine, most of the time with dire consequences. If you are unsure which size swirl flaps you require please