The digital reptile thermometer is a small yet very accurate and reliable temperature measuring device with a great 1 year free replacement warranty. Keeping tabs on environmental conditions is key to good health for your reptiles and making sure you have a quality thermometer is now easy and inexpensive. This unit is a must have for any serious reptile keeper. The long 39" probe makes it easy to measure your terrariums temperature gradient. You can move the probe easily from the warm end of the cage to the cool end. The unit and the probe each have a suction cup so you can mount the thermometer on any smooth surface and you can do the same with the probe.