EAO 73-00002.2 is part of a series of light indicators, switches, and keyboards that can be used to provide visual warning or communication over electrical or electronic circuits. This particular part is a light indicator with a built-in adjustable time delay function. The adjustable time delay can be used to monitor the performance of an electrical or electronic circuit, with the light indicator activating at preset times after a certain amount of usage. This can be used as an early warning system to help prevent circuit failures or malfunctions.