John Guest Speedfit Underfloor Heating Manifolds are Manufactured to the highest standards, John Guest Speedfit LowFit? Underfloor Heating Manifolds are made from stainless steel and are available in a range of sizes from 2 to 12 ports. Fast and simple to install, John Guest Speedfit LowFit? Manifolds uniquely feature John Guest Speedfit Speedfit push-fit connections and come with a pre-mounted bracket and vibration isolation mount. Manifolds can also be assembled to suit left or right-hand supply. Each manifold is supplied fully assembled with flow and return rails, adjustable flow meters, an automatic air vent and fill valve. Protective dust caps are supplied on the return rail, which can be removed when installing circuit actuator valves to open and close the flow of water to each pipe loop.