Two valve manifold is designed in a single block with male or female screwed inlet and outlet ports combining isolation valve and calibration / vent valve. Generally used on static pressure Transmitters, Switches and GaugeTypes of Manifolds. The two main types of manifolds include a single-piece design, and modular block design. A single-piece design is meant to support all necessary valves within a system, and is made up of all passages within the system, in one piece