hydraulic seal kit
In addition to preventing fluid loss, oil seals also protect machinery from external contaminants such as dust, dirt, and moisture. These particles can cause significant damage if they enter the inner workings of equipment. The presence of a well-functioning oil seal eliminates this risk, fostering a clean operational environment.
20x35x7 oil seal

Civil engineers in Rome invented the concept of underground sewer to rid their cities of plagues caused by human contact with waste. Their water sources that they used for consumption were also contaminated as they served as open sewers. The underground sewers made sure that that waste stayed out of reach of humans and was deposited by these sewers further downstream. For periodic cleaning, they also provided access ways that were covered with stone lids that we call manholes today. Incidentally, these stone access way covers are still seen in Jerash, Jordan which was a Roman city in the old days.