Precision 370018A Oil Bath Seal Three piece cartridge outer wall provides maximum strength to support installation with any wheel seal manufacturer's installation tool The ribbed design also allows the seal to be easily installed without tools, and grips the seal bore so the seal cannot back out once it is seated Oil resistant Nitrile provides a tough, abrasion resistant elastomer Primary sealing lip is a spring loaded hydrodynamic lip that pumps oil back to the bearings Axial Dirt Lips have fixed interference that excludes dirt and prevents contamination