This is a very useful gauge to measure reduced pressure. It covers the range 0.01 to 0.001 mm of Mercury. It is usually employed in conjunction with vacuum pump. It has direct reading, compact and is charged with only 11 to 12 ml of mercury. To know the vacuum in the system the gauge must be tilted to vertical position. After knowing the pressure tilt the gauge to horizontal position (Rest Position).
Range : 10 mm x 0.01 mm & 1mm x 0.001 mm