The Flammable Vapor Sensor is a design innovation to detect volatile elements in the environment and launch a troubleshooting mechanism, typically to prevent a gasoline spill within your water heater. The FV Sensor kit includes OEM genuine factory authorized parts to ensure high-quality and safety of your equipment. Detects harmful elements such as gasoline spills OEM genuine factory authorized part FV Sensor Kit AP13447-3 (1) – FV Sensor AP13450-3 (1) – Cap Plug AP14446 (1) – Wire Tie – 6 in. AP15048 (1) – FV Sensor Replacement Kit Installation Note: Water Heater parts and accessories should only be installed by qualified technicians. Failure to understand and follow the manufacturer’s installation and use instructions may result in fire or explosion, electric shock, property damage, injury or loss of life. It is your responsibility to seek professional advice when installing and using these parts and accessories.