The MSP-100 portable pump is based around a Hydrostal Screwcentrifugal impeller. This type of impeller combines the properties of a screw pump with those of a centrifugal pump. The low liquid velocities in the pump result in low shear forces. This makes the pump suitable for liquids which have to be treated carefully and without too much motion and turbulence, in order to avoid emulsifi cation such as water-oil mixtures. The last property makes the pump perfect for oil-recovery operations and it is for this reason that several coast guards have standardized on this type of pump. The pump can be delivered in an aluminium version. A bronze version is optional.