WaterSense Listed. Neoperl 1.0 gpm, dual thread aerator( Dual threaded to fit both male and female ends). Best quality and performance at a lower cost. NSF 61 approved. Aerated stream produces a larger and whiter stream that is soft to the touch and non-splashing. Pressure compensating for a consistently even flow. 15/16" standard male and 55/64" standard female threads.