The sealing lip of the RST-D is more heavy-duty, so it can cope with pressures of up to 10 bar at slightly lower rotation speeds.

Also, Viton has the widest range of resistance to chemicals. It’s resistant to several chemicals like silicone oil & grease, mineral & vegetable oil, aliphatic, chlorinated hydrocarbons, methanol fuels, and so many more.
Posted by on 31st May 2019
Stainless steel sheet
(JIS* SUS304)
5. Sealing the grease container when not in use reduces the risk of contamination.
Standard 3760/3761
Oil seals, also known as rotary shaft seals or lip seals, are a specific type of gasket designed to prevent the leakage of oil or other fluids in rotating shafts.

front valve cover gasket. Once the old gasket is removed, the new gasket can be installed and the valve cover reattached to the cylinder head.