Review on Accurate Multi Parameter Calibration with Apera Instruments AI413: Maximize Precision and Efficiency by Guillo Tilden

The instrument is well built, incredibly easy to use and has a fast response time. The included carrying case is handy (as are the sample size buffers). The guide is actually very helpful and also in regards to using other sensors, accuracy, cleaning, storage, maintenance, calibration etc. My only guess is that the plastic protection around the glass bulb seems a little flimsy, nothing on my unit did. t break, but it seems like it might be possible.