Displays actual pressure and % of air remaining in bottle so you know exactly how much air is left in the bottle Programmable for different size bottles and alarm settings. Works with any air bottles. Alarm trigger point is programmable. Displays Air Pressure in PSI, kPa, or Bar - program the unit to display the desired unit of measurement Audible and visual alarm for Low Air Warning Multiple remote displays using FRC datalink Photo sensor detects ambient light and automatically adjusts LED intensity Uses pressure sensor, not a switch Built-in self test features