Higher ratio oil pumps provide additional capability when dealing with long distance oil dispensing, higher viscosities, unusual line restrictions or a combination of these factors. The 21400 pump is a 8:1 ratio pump with flow rates up to 5.5 GPM while the 21500 is a 13:1 ratio pump with a flow rate of 4 GPM. These are both universal stub pumps that can be easily adapted to fit most any tank or drum application.
