Lifegard AF-94-19 Mecanical Filter Modules, Double Capacity 0-30 PSI/Bar Dial Pressure Gauge indicates when to clean cartridge and manual Air Bleed eliminates unwanted trapped air Cartridge traps particles from 20 microns down to 5 microns; Inner pleat supports prevent pleats from squeezing shut providing longer filter cycle In many cases, single, double and triple capacity modules can be used with great success in higher volume applications Inlet Port 1 1/4-inch Slip/3/4-inch FPT; Outlet Port 1-inch Slip/3/4-inch FPT; Port size dimensions listed are pipe size; SLIP equal to PVC solvent socket type fittings All Lifegard Mechanical, Chemical, Heater, and UV Sterilizers include 3/4-inch threaded reducing bushings if threaded installation is desired