The Toro's 179-2490 (9-6807) is a 570 nozzle body specifically for Toro's 570Z series pop-up sprinklers. It accepts 570 nozzles that feature a matched precipitation rate (MPR), which ensures all similar nozzles in the sprinkler system apply water at approximately the same rate. The 570 nozzles are pre-installed with Pressure Compensation Discs that conserve the water but virtually eliminate excess misting, preventing evaporation and dry spots. This shrub body has only a 1/2" female thread on the bottom and on the top, which is compatible with any 570 series nozzle.