About the Rainbird RVAN1724 Irrigation Yellow Rotary Deflector, 17 24 Foot RadiusRotary Nozzles provide unsurpassed design flexibility and highly efficient water distribution from 17 to 24 feet. The newest addition to Rain Birds line of waterefficient products, Rotary Nozzles help reduce water waste and make it easier to design systems. The Rotary Nozzle is a truly remarkable innovation with a low precipitation rate, highly uniform distribution, and increased radius range, all in a nozzle which fits on a Rain Bird spray head. Selecting the correct nozzle is one of the most crucial, yet overlooked, elements in irrigation system design. Choosing the correct nozzle, whether its for a spray head or a rotor, is easy if you take the time to study the nozzle charts in a manufacturers product or online catalog and select one that best suits your needs; irrigation equipment manufacturers have put a tremendous amount of effort into developing nozzles to fit almost every application: For slopes and compacted soils, select a nozzle with a lower precipitation rate. For windy areas, select a nozzle with a low nozzle outlet trajectory. To achieve even water distribution without having to separate partcircle from fullcircle sprinklers, select a nozzle set that features a matched precipitation rate. Another way to ensure uniform watering, if youre working with spray heads, is to select nozzles that have an undercut nozzle. These nozzles have an second, undercut orifice for watering closer to the head. For flexibility with spray heads, select a nozzle with an adjustable or variable arc. Because nozzles are designed to work within a wide range of pressures, it is important to ensure you have the correct pressure at the base of the nozzle.Too much pressure, as is commonly the situation with spray heads, will result in misting. Misting creates a reduction in the radius of throw and you may experience uneven coverage, and cause wet and dry spots.