Proster Handheld Digital Anemometer - Portable Wind Speed Meter CFM Meter Wind Gauge Air Volume Measure with LCD Backlight for Outdoors Sailing Surfing Fishing

So far, happy with this instrument. Have not had it long but it is easy to use and is providing good wind speed measurements. The data is used for reference on the race committee boat at sailboat race events. It is light enough to stuff in a jacket pocket but it is not small so I'm talking about a big pocket. If it proves durable it will be a great value. The only nit pick is that it uses a 9v battery so need to have a spare on hand. Nothing I own uses 9v except this. It would also be nice if it recalled the last Unit when turned off instead of having to reset it each time. It probably saves battery by not having persistent memory but the Knots unit is the last one in the cycle so every use requires a bunch of button presses. Leaving it on is an option but that uses up the 9v battery more quickly that it's worth.

Good Value, cant go wrong with this, This is a must have, it does everything, i needed this years ago, and always wanted one, now, i use it, and i still cant go wrong. for an Hvac and Refrigeration Guy, it is a must have, and this one here, good value, good product, accurate, a must. I am light years ahead of the game now.

UPDATE: The seller replaced the defective unit at no charge. BEWARE! Huge price drop a month after purchasing, and on other items using gift cards having the item drop the amount of the card or more! And to the product's credit, both units read the exact same in all modes when put side by side. I tried the MPH function and it was right-on with the car's speedometer at 15 and 20 MPH. As the user manual correctly states, the angle to the wind is critical. However, it has the exact same problems as the first unit. The decimal point, in the CFM mode, disappears as soon as the impeller starts spinning, and the displayed numbers have no bearing on the known fan output. ORIGINAL: The impeller blades are not well balanced, and the main use I need it for is measuring CFM from fans, and I cannot seem to find how to do it, even when it says CFM. My 5.5 CFM fan reads 5300+, and my 7.4 CFM also reads 5300+, and my 30 CFM fan reads something like 1000. Another curiosity: In the MIL/hr mode it says around 4, while the trees around me are bent over and leaves blowing. Yes, I know enough to pan the sensor in the correct direction, right under the weather vane. Also, no threaded base or lanyard to screw into it. Nothing like physically seeing and trying something before you pay. Also, you have to use a screw driver to open the battery compartment, as opposed to a snap-in cover, for the 9 volt battery, which is very difficult to press in on both units. I really want the CFM mode more than the other metric units. Finally, the specs say the accuracy plus 5 digits.....what does this mean? There are only 4 digits. UPDATE: 1-2-19: Never hearing back from the seller on how to read CFM, I wrote it off, but some genius posted a necessary formula....not mentioned in the manual. Take the area of the fan, diviede it by 144, and mulitply your CFM reading by that. However, I then had to divide by 10 and do get ballpark readings (10%) to the fan specs!

I fly drones every day. Accurate wind speed is very important to me because knowledge of the wind speed and the second to second variations in wind speed are allow me to decide how to safely pilot my drones without crashing them or having them be blown away.This device is very sensitive and accurate whether measuring a 1 mph breeze, or a 12 to 35 mph gust. I have now used it for 56 consecutive days of flight and the 9 Volt battery is still holding a strong charge.Size: 6.5" tall; 1.5" thick; and 3.5" at its widest. The handle is 2.5" wide and 1.25" thick. Has a nice case. Fits well in my flying bag. Fits well in my small man's hand. Feels good in the hand.Weight with batteries is 7 oz.Construction: solid impact resistant plastic with heavy duty rubber grip in handle part.Impeller blade: 8 blades which rotate freely with the slightest breath.Screen: 1-1/8 × 1-3/8 inches. LCD which is very easy to read. Backlight is easily clicked on for low light situations.Sounds: makes nice chirps when turned on and when functions are changed.Functions: Easily switched between all the functions. I only use it for measuring wind speed in mph or kilometers/hour. Also, measures in knots. There are other functions listed by seller, but I do not use them.In summary, I am impressed with the quality of the build, its reliability, its ease of use, the readability of the screen and its portability. I can't be without it.Good going on a fine product at a great price.

This is a clean good sturdy unit with multiple functions, I am very pleased with this product. It is easy to use and robust and works great. I use it on my sailboat in the ocean to measure wind speed in knots. Its very accurate and reliable, I tested it driving in the car 30 mph with the unit out the window. Went up to 55 mph, reads good wind speeds. You can't beat this unit for the price.

This anemometer works exactly as described. I have used it to measure air flow through my supply and return duct system. It has been excellent so far. It gives consistent results even with retesting. I like that I can set the flow area since I use two different air hoods for this. I can highly recommend it. The only improvement I would like to see is that when it powers down on its own or when you turn it off, it should remember and keep your current settings. Just keep in mind you have to reconfigure your setting each time you turn it on/off. This is not a big issues, because it takes less than a minute to do this. I can recommend it highly and would purchase again.