AbbreviationsMB - Mounting Boss for MC-1A Bracket (not included)MM - Meter Mount for Differential Pressure Gauge (not included)IB - Integrated Bracket, no Extra Wall Bracket NecessaryQC - Quick Connect, John Guest™ Push-to-Connect Fitting3G - Third Generation Style Housing, Newest Design Available PR - Pressure Release for Easier Filter ChangesSS - Stainless Steelw/ - WithClick Here To View Slim Line Series Specification Sheets