Sparex source: https://us.sparex.com/o-ring-3-16-x-2-bs329-70-shore-1955.html Product: O Ring 3/16'' X 2'' (bs329) 70 Shore - Sparex S.1955 SKU: S.1955 Listing note: Material: Nitrile Rubber 70° shore hardness. For general use at temperatures: -40°C to +135°C. Detail enrichment pending: OEM cross references, fitment, catalog pages, and full specifications.