Try this thermometer to find out if it does. I use this thermometer to measure spikes in my incubator. THe spikes that happen when I'm not looking. THis thermometer increases in temp but not decrease, at least not without a few hard shakes. Geratherm mercury-free Oral thermometer. Made in Germany. Found at Walmart $5-6. THis is a glass type thermometer that reads a narrow range of temp about 95-106. ANd very easy to read because a full 9 ticks between each full degree. It seems to be very accurate: I bought 3 and they measured the same during calibration.