The Sun-Mar Centrex 1000-NE is ideal for light to medium seasonal use. It is specially designed for narrow spaces, being only 22.5 inches wide. The Centrex 1000-NE is a non-electric unit for those with no continuous 110 volt power supply. All Sun-Mar composting toilets incorporate a patented Bio-drum™ which ensures fast and odourless decomposition. Saves thousands of gallons of water, while recycling waste into safe useable soil. The unit is shipped fully assembled. An ultra low flush toilet is required for use with this unit (sold separately). Seasonal capacity: 4 adults or families of 6.