Basic Survival Kit
Now having a basic survival kit doesn't make you Bear Grylls or any other survival expert, but it is important to have one with you in the backcountry, as many lost victims may have stayed alive long enough to have been rescued if they only had a few basic essentials with them.
Below is a list of the minimum items you should have along with you in the mountains, and they should be sealed in a waterproof container. You can also buy nice basic kits by Adventure Medical Kits.
liquid filled compass
fishing gear (string and hooks and maybe simple lures)