Not just cheap plastic part. The nozzle itself is plastic, not brass, as with single nozzles available. But it helps and is in spite of the high price hardly "just" produce itself in DIY. The beam is directed more in width, as at the conventional circular nozzles for spraying plants and there is less spread by wind. The whole width of the screen is, however, not completely sprayed evenly, I have the impression. This probably can be but by such a simple construction, can not achieve better.
