Works with 123 batteries that have been drained below the level where they are useful in a flashlight, but they can keep this incandescent bulb aglow putting out 3 lumens for many hours. Used for a couple of days during an ice storm power outage, before we got our generator. Amzing how long it burned on just two batteries. It’s just been sitting on a shelf since that incident, except when I got it out for these pix. Holds up to 12 batteries, but only two at a time are required to power the lamp. It is also designed to just be a carrier for 123 batteries. You tuck the lamp assembly away inside when its just holding batteries. Price of $55 includes USPS parcel shipping in US. Batteries not included. PayPal only please.