The NMT NGR Series Vent Limiter (VE1000-VL0500) is designed for indoor installations with all NGR Series gas pressure regulators (NGR02, NGR04, NGR06, NGR08). The vent limiter limits gas flow in the event of a diaphragm rupture. The vent elbow component allows the regulator to be positioned in various orientations while keeping the vent limiter upright in its required vertical position for proper vent limitation. Installation takes only seconds. The vent limiter must always be installed in the upright position to function properly.