Batteries load like a PEZ dispenser (similar to the FLITELite Microlight). The light uses 3 Silver Oxide 389/390 batteries. The battery door is a silicone molded part that has excellent elemental and drop resistance. The 3mm LED is recessed inside inside the body of the light. This means less lateral visibility, ideal to reduce canopy glare and increase light discipline. It was developed to accommodate the F-22, and was tested with several rotorcraft types. NVIS White is a full spectrum light - that means great goggle compatibility with no missing colors. Helps protect your night vision when flying unaided - our color of choice when we fly. It has an integrated, battery saving 10-minute auto-off. Simply touch the button and light will shine wherever the pilot points. Press and hold the button and light will cycle from low to high bright - release when the brightness is set where you prefer and that setting goes into memory. If the battery power is low - the light will blink when powered up to advise it is time to change the batteries. Perfect for complicated lower panels, radio tuning, and searching for circuit breakers.