1227 is a dual range Flex-Tube® U-inclined manometer(metric units). It is a versatile, low cost manometer that can be used to read high-range pressure on the right leg or as an inclined manometer to read low-range pressure on the bottom leg. It is made of a sturdy, clear plastic and offers direct readings as a U-tube or an inclined gage. Magnetic clips are attached to the unit to hold it in position on any steel duct surface and instructions are conveniently printed directly on the scale. It is used in fan status and filter monitoring.