Economical and compact peristaltic pumps provide a constant flow of liquids or gases at a fixed rate. Four factory-pre-set RPM pumps are available and four different silicone tubing I.D.'s can be used in each pump to obtain different flow rates. The self-priming pump head is made of molded polypropylene and has two rollers. Unit will work against back pressure up to 25 PSI continuous and 40 PSI intermittent, making it ideal for filtration applications and for work with viscous fluids. Shipping weight: 5 Lbs. 115 VAC.