They are usually close coupled to gear drives in "block" style. They handle abrasive and corrosive materials and are available in a range of materials, including cast-iron, cast-stainless-steel, and Halar-coated bodies. Wetted metal parts include three grades of stainless steel, tool steel, Hastelloy, and titanium. Run dry protection and adjustable stators are available. They can also be equipped with hydraulic drives.