NEOPERL's Perlator 2.2 GPM 15/16 in.-27 regular Male aerator is flow restricted. The exterior rotating sleeve of the aerator can only be installed and removed with a key so it prevents tampering. This makes the aerator ideal for use in bathrooms in commercial and multi-family buildings. This aerator features an anti-clogging red dome screen that filters sediment. The Patented single piece construction is virtually unbreakable and lime resistant. Aerated stream provides a soft to the touch feel. Solid brass, lead free housing with a chrome finish. Due to state regulations this item cannot be sold in California.Vandal proofAerated streamSolid brass with a chrome finishLime resistantRestricted flowANSI/NSF 61, ASME A112.18.1M, CSA B125, AB1953, S-152