The Floor Bracket Package B adds a few accessories to the Pkg. A which add convenience and uses. The first is a Base Mount. This is the rectangular thing on the left. Once bolted down to the truck bed, trailer, or tool box, the Base Mount acts as a lockable docking station for your Floor Brkt. and Power Tank. The idea is to save you time and keep your Power Tank from getting knocked around or stolen. The light aluminum Floor Brkt. holds the CO2 tank at the perfect angle to expel vapor yet provide a super low center of gravity for maximum stability. This Package B also adds an air chuck and tire pressure gauge to inflate tires on your truck, bobcat, or tractor trailer. Here's whatelse is in the Pkg. B: Floor Bracket, a 25' braided SuperFlex hose, the fittings, our 0-200 PSI SuperFlow HPx regulator, the Power Grip regulator guard, a15lb. capacity aluminum CO2 tank with protective boot, and a regulator cover.