Nice Compatibility: these paint sprayer tips are compatible with most airless paint sprayers, and 109, 209, 211, 311, 315, 415, 417, 515, 517, 621 correspond to the nozzle diameters of 0.009 inches, 0.011 inches, 0.015 inches, 0.017 inches, 0.021 inches, and the range is 4 to 14 inches Considerate Combination: you get 10 airless sprayer spraying machine parts of different sizes, namely 109, 209, 211, 311, 315, 415, 417, 515, 517, 621; Each is equipped with an airless nozzle and a nozzle seal; Different model combinations can better meet your different needs Broad Utilization: tips with a variety of models to choose from to meet your different use needs, such as paint, furniture, fences, home decoration, industrial fine paint and decoration and so on; Also they are applicable for surfaces and materials, such as industrial enamel, varnish, water based paint, internal and external wall latex paint, fireproof coating Easy Installation: no tools are required to install, and airless nozzle