There are two types of cassettes offered—Click’n’go™ and Pressure Lever cartridges. Click’n’go™ cartridges feature automatic occlusion for simplified use, fewer tubing changes, and reproducible results. Install cartridges in one direction for low pulsation; in opposite direction for higher counter pressure. Pressure lever cartridges offer the user the opportunity to manually adjust the back pressure experienced by the tubing / pump combination. The Click-N-Go design allows for tubing to be used in systems that have up to 1 bar of back pressure exerted on the tubing. The Pressure Lever design allows for system pressures up to 1.5 bar. Cartridges are available made of POM-C or PVDF.