ThermPro TP-50. This is a really nice accessory to have around wherever you place your Evap-o-watt. It shows you the ambient conditions that explain why your LED's are flashing at the speed they are. The lower the humidty (at a given temperature), the faster they will flash. Also, you can see how much the humidity is increased in the area surrounding your Evap-o-watt by moving the meter a few feet away, measuring the difference between the more distant conditions and those close up. Allow enough time for the meter to adjust to its location each time you move it.
