Heat measure

Question
Hello,
I have 2 Kenyan Sand Boas and since they naturally burrow and remain close to their heat source I am worried the heat pad I placed under the tank may become to hot for them. I'm not use to this problem since all of my other snakes are not burrowers and these little guys are my first of those kind. Is there anyway item to measure the temperature of the tank bottom?
Thank you

Answer
You will need a thermostat, just set the temperature you want the mat to have. You will also want a thermometer with a probe to read the temp in the area of concern. I would also suggest a heat gun for taking the temps through out the cage.
http://lllreptile.com/store/catalog/reptile-supplies/thermometers-thermostats-an
JRFK