There are many models of nozzles, and the first number refers to the spray angle, such as "5" representing a 50 degree angle.

The second and third numbers refer to the nozzle diameter, such as "17" representing 0.017 inches.

The nozzle with model number "517" will have a spray width of about 40cm when it is 30cm away from the spray surface.

The nozzle with model number "631" will have a wider spray width of about 60cm.

Of course, low-power airless sprayers are only suitable for selecting smaller nozzle models to ensure spraying speed and surface quality.