iKool Modular Two Function Sensor Faucet Instant Replacement - Modular design makes maintenance and future replacement easy Intelligent Sensors - Two motion sensors. Front for quick on/off . Top for continuous flow. Easy Installation - Install initially like any standard 4" centerset model. Low Power Consumption - Uses 4 alkaline AA batteries. 250,000 plus times of on & off cycles. Award Winning, Fully Certified and Multinational Patented