The difference between the 4 swirl plates is the droplet size. The blue swirl plate has a very fine droplet spectrum, the grey a fine droplet spectrum and the black swirl plate has a medium droplet spectrum. The white swirl plate has a medium droplet spectrum and is giving a full cone spray.
A large drop adaptor (371077) is available for the grey swirl plate. This adaptor changes the droplet spectrum to very large droplets.
HARDI 1553 Cone nozzles are used with one of the four available swirl plates for hollow cone and full cone spraying. The hollow cone nozzle can be used for pesticide application on boom sprayers, mistblowers or knapsack sprayers. The HARDI 1553 cone nozzle can also be used without swirl plates for solid stream application