The OMEGA ® HHF300A Portable Air Velocity Meter is a precision microprocessor-based anemometer system. Because of its unique velocity sensor and the microprocessor, the HHF300A is capable of reading over an exceptionally wide 60 to 6800 FPM range. Other features of the HHF300A include averaging over a 2-second interval. Special Velocity Sensor The HHF300A utilizes a unique sensor to provide air velocity measurements over a wide range. This compact, 1" diameter sensor, combined with the handheld readout, can measure air velocity from 60 to 6800 feet per minute. The sensor is permanently attached to the HHF300A by a 1.5 m (5 ft) extension cable, which allows the probe to be remotely mounted in hard-to-reach spaces. Also, the two extension rods, which attach directly to the sensor, permit measurement in high ductwork and air shafts.