The Weathermatic Bundle SL800 Water System Controller is a 4 Station Controller 4-zone base model, expandable to 8 zones using SLM2 2-zone hot-swappable modules (Indoor rated) with 2 run modes, 4 programs, and 8 start times. Weathermatic products are designed with efficiency in mind. The typical Â½-acre commercial property uses about one million gallons of landscape water per year. On average, properties exceed the landscape watering need by about 38% - or 380,000 gallons. Many properties overwater by as much as 60% - pouring hundreds of thousands of gallons of clean water into our streets and sewers. Weathermatic's primary goal is to reduce over watering wherever possible.