https://www.sanpingmachinery.com/products/oil-seal/ The custom made oil seals is generally used to seal the oil, it is to isolate the parts that need to be lubricated in the transmission parts from the output parts, and will not let the lubricating oil leak. Static seals and dynamic seals (generally reciprocating motion) use seals called seals. The commonly used materials for oil seals/seals generally include the following materials: nylon (PA), nitrile rubber (NBR70°, NBR90°), fluorine rubber (FKM70°), polyurethane (PU), polytetrafluoroethylene (PTFE), etc. Seals can be divided into: piston rod seal, piston seal, buffer ring, dust seal, rotary seal, pilot valve seal, wear ring, etc.