The Bacharach MZF Draft Gauge is a portable manometer that enables contractors and technicians to quickly and accurately measure draft. The pointer's movement over scale is in direct proportion to the magnitude of the draft at the test point. The MZF is ideal for many residential, commercial and industrial applications including measuring furnace draft and pressure drop across air filters, checking flue pipes, chimneys, draft regulators, basement ventilation and more. The highly sensitive MZF Draft Gauge requires no liquid or tedious leveling like other manometer types; this dry type instrument is always ready for immediate use.