Abstract: A direct passage manometer includes a body into which at least two rectilinear channels open into a recessed curved surface at a central portion thereof. A diaphragm seals the curved surface at the center of the body and is fixed in place by a load cell. The load cell has a movement amplifying device and indicator mounted thereon. The movement amplifying device rests on the diaphragm, connects to the indicator and is fixed in place by the load cell. The opening holes of the two channels are elliptical in profile and machined so as to avoid any retention zones.