Each air spring has a separate air line. This four corner system provides maximum versatility for clowning or weight control. The vehicle can be leveled side-to-side or front-to-rear. This is the best kit we sell. 1 - Viair 450C Chrome Compressor 1 - Pressure Switch 110-145PSI 1 - Air Lift 5 Gallon, 8-Port Tank 8 - Air Lift 3/8in Chrome 300PSI Electric Valve 2 - Dual Needle Gauge 200PSI 4 - Rocker Switches 3 - Fuse Holders with Cover 3 - 15 AMP Spade Fuse 6 - 30 AMP Spade Fuse 1 - 40 AMP Heavy Duty Relay 1 - Single Relay Socket 50ft of 1/2in DOT Synflex Air Line 50ft of 1/4in DOT Synflex Air Line 2 - Thread Sealant Packet 1 - Air Line Cutter 1 - 1/2in Street Tee Fitting 2 - 1/2in NPT to 1/4in FEM Bushing Fitting 2 - 1/2in NPT to 1/8in FEM Bushing Fitting 1 - Drain Cock Fitting 1 - Inflation Valve Fitting 1 - 1/2in NPT Hex Plug Fitting 4 - 1/2in NPT to 3/8in FEM Bushing Fitting 4 - 3/8in Street Tee Fitting 8 - 3/8in NPT to 3/8in NPT Straight Fitting 4 - 3/8in NPT to 1/2in Line Elbow Fitting 4 - 1/4in NPT to 1/2in Line to 1/2in Line Tee Fitting 4 - 1/4in FEM to 1/4in Line Straight Fitting Chrysler 300 - Front Includes: left and right air struts Chrysler 300 - Rear Includes: bags, brackets and shocks for both left and right sides Check out the air kit upgrades section at the left for upgrades and additional items.