Oil-lubricated vacuum pumps achieve a very high level of the final vacuum of 99.9% (= -999.5 mbar max.), generate high volume flow and can sometimes be used even in moist or humid ambient conditions. Moreover, they are suitable for continuous operation.
Oil-free or non-lubricated vacuum pumps generate high volume flow and a high level of vacuum (up to -880 mbar max.). They are particularly suitable for dry air, when the vacuum level changes frequently, and also for constant low-vibration extraction.