The document discusses a 5000 Series PRS Rotor sprinkler head that uses in-stem pressure regulation to ensure optimal performance at 45 PSI, eliminating fogging and misting and head-to-head pressure variation. It notes that every 5 PSI reduction in pressure saves 6-8% in water usage and independent testing confirmed the 5000 PRS provides 15-45% water savings compared to non-regulated sprinklers. It asks how much water is being wasted at 65 PSI and 75 PSI, compared to the 5000 PRS at 75 PSI.