Made from tough plastics. Used both for testing pipework installations with air for leaks before the introduction of gas & for checking & setting correct gas pressures on domestic & commercial appliances. Extruded cover slides off & may be clipped over the base for standing the tool vertically during use. Hanging tab permits vertical hanging from suitable protrusions. Marked in millibars the scale adjusts for zeroing water level. Plastic U Tube. Size 900 mm. (36 in.). Capacity: 90 Millibar. Fitted with nitrile hose for testing LPG (Liquified Petroleum Gas).