MARSHALL EXCELSIOR Flow-Longer Propane Kit - The Flow-Longer Propane Kits are designed to connect small, portable appliances, normally fueled by disposable LP-Gas cylinders, to the existing LP-Gas fuel supply of a recreational vehicle, cottage, backyard patio, etc. without interrupting the supply of regulated fuel to the system. Flow-Longer eliminates the need to purchase an extra LP-Gas cylinder or several small, disposable type cylinders. FEATURES: Brass tee connection (ME415) .9 GPM excess flow male hard nose POL x female POL x 1in-20 male. 12ft hose (MER421-144) 1in-20 male x 1in-20 female. Includes installation instructions and a convenient reusable box for storage. Note: The tee fitting must be installed between the vapor withdrawal valve on your LP-Gas container and the pressure regulator. This properly places the tee fitting in the high pressure portion of the LP-Gas system. Gas connections to the tee fitting are not designed for movement or rotation after installation. Flexing, twisting, or vibration should be avoided. Warning: An excess flow valve will not activate if there is a break or leak downstream of the valve that does not equal or exceed the closing flow of the valve or if the excess flow valve installed exceeds the flow capacity of the system.