Neoperl Dual Thread 1.5 GPM Water-Saving Faucet Aerators (6-Pack), 706347 Standard Size: Internally and externally threaded with 15/16 x 27 threads outside and 55/64 x 27 threads inside Save water and energy when compared to standard 2.2 aerators Aerated Bubble Stream WaterSense listed Meets Low Lead Requirements