I carry quite a few safety/ survival items. Last year I started to carry a SpotII since I hunt alone for 7-10 days at a time . There is -0- cell service where I hunt and I will tell you the thing works. I was sending 1-3 messages a day letting family know all was well. Everyone of them were received. The coordinates were dead on when I checked them on the map and GPS.
I carry two space blankets in my pack and keep a few extra in my truck.. I have been known to stay on the elk and the space blankets are light and do a pretty good job when you sleep out in the open or at a makeshift camp at night. I have used them multiple times. I always carry two days worth of food in case I don't make it back to camp or something happens. Water I refill every time I have a chance as I go through lots of water and you really don't know when you might be able to fill up again. I always carry a first aid kit with whistle and it includes (Celox sp?) Two ways to start a fire. Extra meds if you use any. I always carry 550 cord extra batteries, one headlamp Streamlight 14512 that strobes, a small but good flashlight Fenix PD32. 1/4 roll of duct tape. Extra socks. I also carry a gps but always have a map of the area I am in in my pack with a small compass. I'm sure I forgot something but all the above don't weigh much.