The EFP-6-A is a faucet sensor replacement kit specifically for the ETF-600 and EBF-615 style faucet. The kit contains the ETF-600 and EBF-615 sensor. This sensor can only be used on the ETF-600 and EBF-615 style faucet. All of Sloan® sensor operated soap dispensers and many of our faucet models operate by means of a reflective infrared sensor. This is the most common technology used by most manufacturers of sensor operated soap dispensers and faucets. In this application the sensor emits a beam of infrared light. When a user places their hands in front of the soap dispenser or faucet spout, that infrared light bounces off the user's hands reflecting back to an infrared detector in the sensor. Infrared light, like visible light, will reflect back with greater intensity off brighter and more reflective surfaces. Sloan® optical engineers understand this and Sloan® designs its sensor to work within a general window of reflective environments typically found in a public restroom.