Oil seals are used for automobile engines and geared motors, and are designed mainly to prevent oil leakage from the end of a rotating shaft, or dust intrusion from the outside air.

Oil seals serve to prevent the leakage not only of lubricants, but also water, chemicals, and gas from "gaps" in machinery. Oil seals also serve to prevent the intrusion of dust, soil and sand from the outside air.

Oil seals are indispensable sealing devices and are used in various fields, including automobiles, aircraft, boats and ships, railroad vehicles, construction machinery, farm machinery, petrochemical plants, and electrical home appliances