A small oil separator is designed to perform high oil separation efficiency even further downsized and in a streamlined shape. This has greater importance for modern cars as the engine bays are becoming more crowded. Compactness does not compromise the ability to achieve optimal oil separation with advanced separation techniques which are incorporated in the design. This may include new features like micro channels or multi-stage separation which are housed in a small shell. Small oil separators are widely used in space constrained applications such as hybrids or electric vehicles with limited engine bay space, or in high performance cars where every inch is occupied by other components. They offer an efficient approach to maintaining an engine’s cleanliness and performance without taking up excessive space.