Extech AN300 Vane CFM/CMM Thermo-Anemometer

Used but kept in good condition

If you need reading accuracy but not fine resolution of readings and volume entry, I think this is a decent meter worth considering. If you need high sensitivity and data resolution, as well as responsiveness to very low airflow, this is not a good choice. Also, if you want something user-friendly, I'd look elsewhere.Comes with hard case and batteries.Reliable, accurate readings. I didn't notice any flukes or erroneous readings during testing.Cannot register very low airflow - the sensitivity is low but not low enough.The resolution of the AF reading isn't fine enough.The area setting does not allow for decimal points, which is stupid.Easy to find point of strongest airflow due to the 4" vane.The blades are set at a 45 degree angle, are completely flat with slight texturing, for better or worse.Readings are supposed to be taken from the rear of the vane, which I assume is because the thermistor is set into the hub in the rear. If you don't need accurate temps, you can most likely take readings from the front, except then you can't see the readout.The blades are slightly out of balance, which would require applying nail polish to the lighter ones until the vane no longer turns.The display is large, yet they don't allow for velocity, airflow and temperature all to be displayed at once - only vel. & AF or temp.Limited range of units of measure: 2 imperial, 2 metric.Ambient, but no wet bulb or dewpoint temperature (AN310 has those).The interface has only 4 buttons that are beneath a single sheet of plastic that will eventually crack.The setting for the area being measured is set using a different button than the one used to select hold, min and max.The duration for secondary button functions is longer than necessary.The buttons are not clearly and completely labeled despite adequate space.There are functions that are not properly organized in the manual.No datalogging, or real-time data transfer.No protective casing, which is unacceptable for a field unit, . The silicone gasket that runs over the joint between the front and half will only protect the device if it lands exactly on it, which I suspect it usually won't. The vane cowling is not protected at all.The vane is recessed enough that you don't have to worry about it colliding with anything.No AC power port.The battery compartment door is firmly in place, but not difficult to remove.There is what appears to be a recessed button on the back about 2" above the battery compartment, but it is not documented.Ultimately, there is a lot left to be desired from a meter in this price range, especially given the competition. One computer fan reviewer/tester I know was able to take a cheap BTMeter, add nail polish to balance the vane, and has no trouble with accuracy and resolution...For way less than what this meter costs.