Several people spoke about the accuracy of a thermometer called the Egg-O-Meter on this web site and I bought one. I found that the Egg-O-Meter is very accurate in temperature reading if left in the incubator for several hours to warm up. It read exactly 100 degrees just as my incubator thermometer. One drawback is the size of the artificial egg. I found that it was too big to stay in my bantam egg trays and would fall out when the tray turned. The feature for reading high and low temps is a great service because you can get an accurate guage of the temperature variations in your incubator. I'm satisfied with this product.