The Mark 608IS gas pressure regulator is ideal for low-pressure gas regulation. The self-contained, low-pressure gas regulator is for use on tank blanketing, gas meter inlet pressure regulating, gas burners, and other low-pressure air and gas applications. The Mark 608IS is normally open. The aspirator senses increases in the outlet pressure, causing the large elastomer diaphragm to rise, moving the plug toward the seat. As outlet pressure decreases, the diaphragm shifts down and moves the plug away from the seat to increase flow. The lever, which connects the stem to the diaphragm, amplifies diaphragm forces for tighter shutoff.