Installs Easily On 3/4″ Main Water Lines, Clear Sump, Wrench Included, Patented Shut Off Valve In Cap For Easy Filter Change.  Uses 3/4″ Comp x 3/4″ MIP Fitting.  Uses the Following Catridges #P-5, #CW-F, #CW-MF, #S1-AD, Catridges Sold Separately.