Flow Restrictor for All Shower Heads by HammerHead Showers, 2.5 GPM

2.5 GPM (Gallons Per Minute) Flow Regulator by Neoperl® for HammerHead Showers® Works with all HammerHead Showers products Steady flow rate regardless of pressure, optimal for households with low water pressure The combination of the calibrated o-ring and seating area is accurately calibrated to the water pressure and ensures a steady flow rate within the indicated range. Flow restrictors, such as the HammerHead Showers 2.5 GPM, feature a housing, seating area & precision o-ring. The o-ring shape alters with varying pressure & water flow, staying within the given flow rate tolerance. When no flow/pressure, the o-ring is relaxed (pos. 1); with flow, it's pushed into the seating area (pos. 2), the pressure increases, o-ring shape changes more (pos. 3), & as pressure decreases, o-ring shape returns to pos. 2 & 1.