"Perfect for medium to heavy seasonal or light residential use, the Centrex 2000 allows for both a longer composting cycle, and larger waste volumes. The most environmentally-sound method of waste treatment; these toilets use the natural processes of decomposition and evaporation to convert human waste into a useful fertilizing soil. These units are odorless, due to the venting system. When used seasonally by up to 7-9 adults, compost will normally only need removing annually each spring. The Centrex 2000 features a 370 watt thermostatically-controlled heater in a sealed compartment under the unit and a 30-watt turbo fan, with a 2"" vent stack to remove evaporating liquid. The Centrex 2000 may be used with one or more Sealand low flush toilets (not included). Ideal for medium to heavy seasonal or light residential use Converts human waste into a useful fertilizing soil 370 watt thermostatically-controlled heater 30-watt turbo fan"