The screen does not stay lit. Makes it hard to read. The instrument is too small to grab comfortably but it does the job.

Would of gave it a 5 star if the batteries were anything other then the coins, it works well and accurate. It's easy to use and understand perfect for cfm checks in hvac systems

I got this to see what the wind speed and temp really is at my desert cabin instead of guessing all the time. I tried a much larger , costly pole mounted AcuRite that never worked after attempt and attempt After that hurt from a bad purchase I figured what the heck, I'll try something handheld and if if does not work the cost of less than 20.00 bucks with free shipping no big loss like the AcuRite was. After a few days of testing while driving holding it out the truck window the wind speed always matched my odometer as well as the temp. Can't wait to be in the desert ( only on weekends unfortunately) I can now not just guess what the wind speed is howling at but know for sure. Thank you Proster. Small, Easy to set up instructions , enxpensive and so far by my few tests works like a champ. Worth every penny not like the 15000 penneys I paid for on something that was to be much better and work but sucked

My initial review was unfair based on my own stupidity Read the updated version and ignore the original.

Piece of junk. No battery compart on the one I got. It has a stamped-in area that looks like it was where a battery compartment was suppose to be but the only way to get into it would be to cut it out with a knife I guess and then no telling if it has the necessary wiring underneath. Have not heard from the mfg. yet but I'm pretty sure I will be outta luck on this one if I have to pay the return shipping to Shenzhen City Guangdong Province China. I'll let you know what they do about it.

UPDATE: Mfg. contacted me the next day after submitting my claim Man do I feel stupid. There is a yellow protective covering over the unit that must be removed to access the battery compartment. My bad. I was in a rush and didn't do a thorough job of inspecting. The stamp on the back is a little deceiving as it appears to be where the battery compartment is. IMO they would be better off just to leave that off. I have not had a chance to take to the range yet but it seems to work in my back yard OK. My thermometer is reads about 2 degrees high which is in their published accuracy listed. Didn't really get it for temp anyway. I changed my rating based on the Mfg.'s quick response. I think this is good value for the money and the Mfg. was very quick to respond. The item arrived ahead of schedule by a couple of weeks or so.

On 11-10-17 I received the new no cost (free) replacement product offered by the seller
for the experience I had with the first one I purchased and returned. See original review below. I purchase a lot of products on Amazon and provide honest reviews for the benefit of future customers and the seller alike. This time I was disappointed at first as I received a defective product but was surprised when the seller offered a free replacement product and rushed it out to me. Not only did the seller have wonderful customer service the product I received the second time works great. Just as advertised. The battery door opened easily and the battery worked. No need to get my own. The yellow protective case is a bit challenging to put on but adds a bother level of protection if you drop it. Not to mention it makes it easier to find in a poorly lite area. It doesn't calculate CFM but it clearly stated that in the product description. This means you'll just have to do so math. Over all it Works and is light on your wallet. I would buy it again.
Product would not work. I even replaced the included battery with a new one and it still would not turn on after holding the mode button for two seconds as the instructions indicate. I would have given this item zero stars bit that's not an option. Buyer beware!