Fenix makes some, big, complicated lights, but they also do a really good job of making small and simple ones as well. The E01 has long been a standard of inexpensive, simple lights. The output on the E01 is not all that great though, so the Fenix LD15 was made for people who want a compact light that still has a good bit of output.
The LD15 is powered by a single AA battery and has two modes, 117 and 8 lumens. 117 lumens does not seem like a ton of light when compared with some of the lights that we offer, but it will still light up a room and even objects 50+ yards away. The lower output is great for when you don’t want a ton of light, like when reading or poking around in your tent.
Here it is in action: