Review on 🔬 Sper Scientific High-Precision Large Display with Enhanced Resolution by Brian Inman

I purchased this meter through Revain.com. It seems to work well and is easy to use. The only thing that would improve this product would be the addition of a bag or two of the included calibration solutions. The meter must be calibrated before use. Instead, SPER sent me a free waterproof stopwatch with my order, which I think would be useful for measuring the growth rate of my plants. But I needed a calibration solution so make sure you buy a solution if you buy a meter as a pH meter is useless without it.