An Oil seals & Gaskets are a mechanical seals which fills the space between two or more mating surfaces, generally to prevent leakage from or into the joined objects while under compression. Oil seals & Gaskets allow "less-than-perfect" mating surfaces on machine parts where they can fill irregularities. It is usually desirable that the gasket be made from a material that is to some degree yielding such that it is able to deform and tightly fills the space it is designed for, including any slight irregularities. A few gaskets require an application of sealant directly to the gasket surface to function properly. Yamaha genuine parts stock a wide range of quality gaskets & oil seals made specially from eco - friendly materials.