We use the Flash Pen mainly for applications in the kitchen and in the baby food temperature control. For this purpose, it is wonderfully suited as compact and practical, the measurement deviations are for this purpose and in the temperature range of 20-120 ° absolutely fine. A star deduction give it for the rapid wear, the first set of batteries (supplied) was after 3 weeks, the second set (also provided) is serving for months. The push button for starting the measurement only responds to very strong pressure, often it does not react. Since then helps only wait a few seconds and press it a little harder. Very rarely, the device jumps amusing between ° C and ° F back and forth - but this is only 2x happened and has resolved itself again.