When the fixing screws of a crankcase are being tightened, the reaction of the sealing element (paste or paper) can cause a deformation of the flatness of the seal. This deterioration of flatness often causes leaks when expansion occurs.
To solve this problem, Paulstra offers a metallic-elastomeric seal.
The metal part consists of a thin sheet. The fixing screws which act on this rigid material haven o effect on the flatness of the crankcase.