The A-955 was especially designed by Lily to mix super low viscosity resins used for crack injection.

The catalyst is injected into the core of the base resin stream by means of an internal nozzle. This unique design frustrates the tendency of a catalyst to cling to the walls of the mixer, thereby avoiding thorough mixing. In addition, the resin is re-oriented by a 180° turn mid-way through the mixer. These features ensure complete mixing of nearly all formulations. The Tempest is recommended for use with low viscosity materials.