Bunn O Matic EQHP-ESP Easy Clear High Performance Espresso Water Quality Filtration System, 422 Gallon -- 1 each.Specialized blend of resin targeted to reduce hardness and alkalinity. Designed speci?cally for espresso applications. Provides 422 gallons of hardness reduction @ 10.5 GPG (grains per gallon) with a service ?ow rate of .5 gpm. Carbon block integrated to reduce taste and odor. Patented Quick Connect valve-in-head design simultaneously shuts off and vents water with .25 turn, allowing for simple and trouble-free cartridge change-outs. .375" FNPT horizontal inlet and outlet ports allow direct or easily adaptable connections to existing plumbing lines. System maximum operating pressure is 125 psi (862 kPa) and operating temperature 100 degree F (38 degree C).