Sadly I found these three gallon ziplock bags with what what I considered essential gear. It's not like these bags served any particular purpose and they were not universal it was a bag of stuff that I needed at one time or another. I think it's important that the items are easy to acquire because you probably cannot get on a plane or Greyhound with them and so any Walmart should be ok and you should be able to discard them safely.
What do I really need.
- shoe repair or a second pair of shoes. I was 5 miles into Big Cypress and lost the sole of my boots. We could not repair them with string, aluminum wire or duct tape.
- foot repair. I recall the littlest blister almost taking me out in NYC.
- light. During a full moon and clear sky you can see a lot more than you expect but on those dark nights you better have a light and a backup with spare batteries.
- fire. I do not know how I feel about fire. Even on the rainiest night you can wrap yourself in something waterproof in your kit. If hard pressed and with a little skill and time you can make a friction fire but the reality is a lighter and/or fero rod makes more sense. I'd say lighter because it's less heavy than a fero rod, cheaper, and more available. Of course you can always accidentally drain the fuel and there are temp limitations where the fero rod has it's limits too. A combo kit with tinder works... but if this is an essential kit it's not the kind of thing you'd bring to a league game.
- toilet paper, wipes, glide, and sanitizer. This falls into the category of just feeling better. One time I put on a new shirt and even though it was just a few hours my nipples were chaffed. Another time when I was heavier my thighs rubbed and chaffed. And then there was my pooper. I prefer the fresh clean feeling.
- med combo like tylenol and advil are great. tums and immodium are important.
- Just one tube of lipbalm or neosporin is enough.
- if you are some place where water is not available or you are willing to carry enough then leave the filter at home. Else go mechanical and or a metal cup.
- checklist. It's a great idea to have a checklist so that replenishing is easy.
What I did not need...
- matches - I have enough fire sources
- waterproof TP box - ziplock is good enough
- tinder for more than 2 fires. You can always make more or use the TP and where the hell are you going anyway?
- batteries - well I just said that I needed two flashlights and if you had fresh batteries when you started then extra is just not necessary. I do like those CR2036 LED rope lights for camp. The batteries typically last 72 hours. More importantly it sets the mood and acts as a beacon. But it's not essential.
- I have plenty of duplicate items so keep it simple
- I'm not sure how I feel about those mini-tubes from gossamer gear. Small tubes are about the same price as the fullsize but if you're ounce counting or wanting to keep things fresh it might not matter.
- water purification - a mechanical filter is best with a prefilter but in a pinch just drink it and get to safety.
In the middle of the road is a different class of problem...
- I do not know if I need a "knife". For many years I went without but then recently I added one with a fero rod in the holder for fun. It was razor sharp and when confronted with a snake that would not be relocated I had to err on the side of safety of the children. I also used that knife to start the bonfire. It was fun but a lighter would have done the trick. I do have a knife in my medkit.
Keep it simple.