Nozzles designed for "optimum" performance - Each complete nozzle has its own built-in spiral mixer, individually designed for each tip size and flame characteristic. Each nozzle is individually swaged to insure proper alignment for uniform flame, sizing and free-flow contour. Orifice sizes are common for all series - Regardless of nozzle series (300FC, 100FC, J), flame characteristic or fuel gas used. This uniformity of orifice sizes simplifies nozzle selection, eliminates chances of ordering the wrong size when changing from one type of nozzle to another.