AV21 is a touchless kitchen faucet adapter with a model for pull-out spouts and one for regular high faucets. It contains two integrated sensors, one installed on the bottom next to the nozzle and the other on the side. The bottom sensor is instantly activated when you come within range of the sensor and automatically turns the water off once you leave or after 60 seconds. For longer use, you can activate the side sensor to turn the water on and off, or water will be turned off automatically after 3 minutes.The device is universal and is Eco Powered and does not require battery, electricity or recharging.