The ASL 203 Mini Fiber Optic Sensor with Mono Port and 24 Volt Connector is a single function switch with a round target area the size of a pencil lead in diameter. It has an adjustable activation range from touch to a quarter inch. The fiber optic switch can be programmed for either normally open (NO) or normally closed (NC) operation. In the NO mode switch activation occurs when an object is detected in the adjusted range. In the NC mode switch activation occurs when an object is no longer detected in the adjusted range. This configuration plugs into any device that has a mono jack port such as; reset/mode change, tilt or a communication device and requires a 24 volt power source (not included). Typical users are individuals with extremely limited movement such as MD, MS, ALS and SMA.