Triage-type oil filter also known as bypass oil filter and fine filter, the road parallel to the internal combustion engine lubricating oil. And design on the filter restrictor holes of a certain size limit oil flow through the oil filter, after letting some oil through-flow oil filter back into the oil pan. Its purpose is to filter out full flow oil filter does not filter out the wear of internal combustion engines, and smaller particles in order to control the level of pollution of internal combustion engines, thus slowing engine wear. This cable for about 10 minutes until all the engine oil filter. Shunt type oil filter oil flow is small, allowing a larger flow of resistance, but high filtering accuracy, can reach 5~10 μ m. When the bypass type oil filter is used, significantly reducing wear on the engine parts.