Forsberg’s Zig-A-Flow aspirators comes in two series, a Model “A”, and a Model “C”. The model selected is product and density dependent.Forsbergs - Zig-A Flow AspiratorPRODUCT FEATURES Separates lights from a column of heavies Used as a waterfall cooler while aspirating lights Collection hoods are available Download Product Brochure:Forsbergs Zig-A-Flow Aspirator Brochure