The Celestron Night Vision Flashlight is a red LED astronomy flashlight that helps preserve your night vision while you read star charts, find eyepieces, or move around your observing site. It uses two red LEDs for even illumination, and a thumbwheel lets you adjust the brightness. The square shape keeps it from rolling off your observing table,  and an attached lanyard lets you wear it around your neck.

Powered by a 9V battery (included). Celestron item #93588.