■Anti-wear agents: Anti-wear agents help protect parts of the engine that are especially susceptible to damage from high temperatures, like cylinder walls, lifters, cams, and piston rings. This additive acts as a protective layer around these components to limit friction in metal-on-metal situations.
What are Oil Seals and how do they work?

oil seal standard.
Corteco is a well-known brand in the automotive industry, supplying top-quality oil seals, including the first Simmerring® in 1929. The range consists of more than 7000 gaskets and more than 6500 OE-quality shaft and valve stem seals.
MH: O.D. wall is a rubber material
HM: O.D. wall is a metal case
MH(S)H: O.D. wall is metal with a reinforced inner metal case
Notes
*1 ASTM: American Society for Testing and Materials
*2 For more details on fluid compatibility, please see the following:


As shown in Figure 1, sealing devices come in two types: contact and non-contact.
Oil seals are among the major contact type sealing devices.
Oil seals are made from multiple compounds and materials. Some of the oldest, still in use today, are leather and felt compounds. The trend in mass production, however, has seen a move towards synthetic rubber or elastomers. Nitrile is by far the most popular material but developments in PTFE have created a surge of interest in buyers needing seals for high-speed shaft rotation applications. Viton is taking over from the polyacrylic and silicone, as it works better in high-temperature applications and has a high-resistance to abrasion and harmful chemicals.