Flow Watch

ITEM # FW450

Flow Watch

Ideal for making precise field measurements of water or air speed (flow rate). Perfect for HVAC/R contractors/technicians and hydrologists

Best For:



  • Displays instantaneous, maximum or average speed + instantaneous, maximum, minimum or Wind Chill temperature
  • Includes fixed aluminum rod for using unit as compact anemometer
  • Optional FW450-12 Windspeed Impeller and FW450-50 Sounding Cable with Water Speed Impeller are available
  • Speed unit options: cm/sec (default), m/sec, ft./sec (fps), mph, kmph, knots
  • Backlit 4-line LCD with 0.4 in. (10mm) high digits
  • Adjustable start and stop times (3 sec. to 24 hr. duration) in Average mode
  • Lap time (chronometer) function
  • F/C switch
  • Completely waterproof and weatherproof
  • Tripod mount


  • Air/water speed measurement range: 3 to 150 km/h (2 to 93 mph); 0 to 999 cm/sec in cm/sec mode
  • Speed measurement accuracy: 2%
  • Speed measurement resolution: 0.1 for all speed units except cm/sec (3 cm/sec)
  • Temperature measurement range/accuracy/resolution: -4 to 158F (-20 to 70C)/0.4F (0.2C)/0.1
  • Operating temperature: -58 to 212F (-50 to 100C)
  • Dimensions of display unit: 6.1 x 2.6 in. (155 x 65mm)
  • Dimensions of telescoping aluminum rod: 3.9 ft. (1.2m) long x 3.9 in. (100mm) diameter
  • Length of telescoping rod cable: 6.6 ft. (2m)
  • Length of fixed aluminum rod: 3.9 in. (100mm)
  • Diameter of air impeller: 0.79 in. (20mm)
  • Diameter of water impeller: 2.36 in. (60mm)
  • Weight of display unit: 7.4 oz. (210g)
  • Power source: Two "AA" batteries (included)


  • Display unit
  • Telescoping aluminum rod with cable
  • Air impeller
  • Water impeller
  • Custom padded aluminum carrying case
  • Batteries
  • Operating instructions
  • 1-year limited warranty

data sheets