I tried this device to measure body temperature and the temperature of boiling water. In both cases it read much lower than the claimed accuracy or +/- 1.8F and +/- 4.2 F, respectively. Do not buy this, or probably similar devices, if you want to make accurate readings. This is an example of getting what you pay for.
The instructions say that there are no user serviceable parts in this device. Consequently, there is not ability to calibrate this device and possibly make it more accurate than it is.