A disposable flashlight uniquely suited to operation in high humidity and water exposure conditions, such as those encountered in search and rescue missions at sea. The bulb, which is preferably a high intensity super-bright light emitting diode, is energized to produce light using a battery connected to it via a switch and an electrical circuit. The switch completes the electrical circuit via an electrically conducting fluid, allowing the electrical current to flow from the battery and the bulb to illuminate.