Common natural gas meter sizes include D-800, 800 and 7000 series by Sensus and GE respectively. They range in size from 10.6 inches x 15 inches to 10 inches x 12 inches.
Natural gas meter sizing is determined by the variable or constant line pressure at the time of installation. It's also determined by the maximum natural gas flow requirements measured in standard cubic feet per hour or British thermal units per hour.
Other measurements such as pulse output; flow direction, including horizontal, vertical down or vertical up; and 4 to 20 milliampere output can also help determine natural gas meter size. Line size can help determine the necessary gas meter size, but it's not sufficient on its own.