SKF Radial shaft seal with metal case and single sealing lip, for grease Radial shaft seals are used between rotating and stationary machine components, or between components in relative motion. HM4 seals are designed with a single metal case. They have a conventional single sealing lip made of elastomer. Typical applications include grease lubricated agriculture machinery. Shaft diameter: 0.313 in Housing bore diameter: 0.5 in Seal width: 0.125 in Maximum operating temperature: 212 °F Minimum operating temperature: -40 °F Rotational speed: 900 r/min Design: HM4 Auxiliary lip: No Sealing lip material: Nitrile rubber (NBR) Type of outside diameter: Metal-cased