Rainbird Half Circle Pattern Rotary Nozzle Type: Rotary nozzle Features: Pressure range: 20-55 psi Spacing: 13' to 24' Low precipitation rate - 0.60 in/hr (15,2 mm/hr) - reduces run-off and erosion. Multiple, rotating streams uniformly distribute water throughout the radius range. Matched precipitation rate across radii and pattern simplify the design process. Maintains highly efficient performance throughout the 20-55 psi pressure range, with no misting or fogging at high pressures.