The Nano-Lux 10280 like all the TnC products is superbly finished and built like a bank vault solid and dependable. These tiny N-cell sized (10280 Li-Ion) mules use the new Cree XPG-2 LED. A mule is a flashlight without an optic so it can produce a very wide beam with perfectly even illumination, these lights are extremely bright and work great as an area light. They have three outputs with a memory mode, and are offered in Electroless Nickel Aluminum, Brass, Copper, Stainless Steel and Titanium. The unit produces about 350+ lumens on the high setting with a smooth on/off twist head operation. These torches will not work with an alkaline AAA 1.5 volt battery. The settings are as follows: High-100%: Medium-30%: Low-5%. The unit will step down to a lower setting when the battery needs to be recharged. The flashlight has a length of about 2 inches and a head diameter of 0.60 inches, the battery tube diameter is 0.53 inch. A split ring is included so you can mount the flashlight on your keychain if you want. Price does not include batteries or a charger, and must be purchased separately.