This thermostat will control up to 4 mats or cables. Rugged construction means it will last you for years to come. Since it's completely waterproof, the unit is virtually impervious to water, soil and chemicals. All you do is connect your mat or cable and set the dial. The thermostat does the rest. This model has adjustable temperature settings from 40 to 100 Degrees and is GFCI protected. It can also be used to control portable electric heaters and heat lamps.