New and exciting tank monitor system. With 3 sensors you get 4 levels. Install, make settings and see the results on your smart phone. Free App for iPhone and Android phones included. You can use Gobius Pro for all liquids and tank materials. 12 - 24 Volts. Choose water, fuel, waste or other fluids. You can have max 9 sensors/tank. Read more at www.gobiuspro.com