This. For your next one I recommend one that has two-point calibration, ATC, +/- 0.05 or better accuracy (0.01 resolution), and a replaceable probe. The ATC is not to check mash temp above room temp, but rather possible a signal of a minimum degree of quality.
Personally, I can vouch for the 8689 pH meter sold by Thermoworks for $70, or Reed for $99 and available direct from China for much cheaper. It looks like it's also available as a white label product from Amazon. Some people like this DrMeter pH meter.
No offence, but those yellow (and other color) $10-20 meters are garbage.