Another tool that assists in survival is a light source. Without a flashlight, low-light work or travel can be very difficult & dangerous – sometimes impossible. Not only can a flashlight allow you to be productive in low-light conditions, but it can also be used as a nighttime signaling device. A good flashlight can also help prevent injuries in dark conditions. I purchased a flashlight with picatinny rail holder for the other side of my barrel. The push button switch on this flashlight is also a compass. Now, I have a means to confirm direction as well. This can certainly be useful in any survival scenario.