As a former Army Ranger who now spends his life traveling by unconventional means, I have learned that there some things that are useful in just about every environmental condition and scenario a person could possibly encounter.

Specifically, over the course of my travels — from kayaking hundreds of miles, to backpacking thousands, across five combat deployments to Iraq and Afghanistan, and during a recent trip through cartel-controlled neighborhoods south of the border — I have found that there are three things I cannot go without.

Just to be clear, this is not an exhaustive list of everything you need for any and every situation. Rather, these are the things that I have found useful regardless of the situation. If you’re on a limited budget, you can go to the bargain bin for these items and still be fine. But if quality is a priority, you should opt for the high end and find something that will last a lifetime.

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Of course, price tags aside, everything comes down to personal preference. The brands that I am recommending here are ones that I have used myself or come highly recommended from people I trust.

A pocket knife that is three inches or less.

A knife is one of the most diverse tools you can carry. It will cut open a box at work, clean your harvest on opening weekend of hunting season, or be your last line of defense in a bad situation.

I specifically carry one that is three inches or less, as this will allow you to carry it most places, keep it concealed, and not freak your coworkers out if you use it at work. Make sure to do your due diligence on the state and/or country you live in or plan on traveling to, as knives over this length can be considered concealed weapons for which you could be arrested for.

What kind should you buy? Personally, I prefer a folding blade as opposed to a fixed blade as a matter of practicality. Benchmade is a good brand that I used to carry and is synonymous with quality and durability, but they are not cheap either.

Unfortunately, I have a bad habit of losing my knife or temporarily not knowing where it is. That can turn into an expensive mishap over time. That’s why I carry cheap four-dollar folders that I find at Wal-Mart now. I can lose as many of them as I want without denting my wallet too bad, and they do the job. Are they as good as my old Benchmade? Nope, but I don’t necessarily need them to be for my normal, every day chores either.

A durable watch with diverse functionality.

U.S. Marine Corps photo by Sgt. Matthew Callahan

A good watch might seem redundant in a day and age that has nearly every man, woman, and child carrying a cell phone at all times. An over reliance on technology is a recipe for disaster though.

Cell phones don’t hold a charge for more than a few hours, they break easily, and depending on your line of work you might not be able to take them into certain places. But a decent watch will almost never let you down. You can take it anywhere, and even use it as a compass in a pinch.

A watch can be as cheap or as expensive as you want it to be, it really just depends on what your budget is and your needs are. On the low end, you can pick up a simple Timex and it will last a long time. I used the same Timex that I bought for $35 for three deployments overseas without fail. If you have a few hundred dollars to spend and want some really great functionality, then you can check out a Casio G-Shock or anything made by Suunto. Whether you are diving in the ocean or summiting mountaintops, these watches are real workhorses and will perform well in nearly every environment on earth.

How do you use your watch as a compass? If you are in the northern hemisphere just hold the watch horizontal to the ground, and point the hour hand at the sun. Approximately halfway between that point and the twelve o’clock mark will point to the south. This is just one of many non-traditional uses for a watch, so do your research. This kind of multifaceted utility makes it an automatic mainstay on the every day carry list of anyone who takes preparedness seriously.

A good pen and notebook.

Australian Defence Force photo by Cpl. Jake Sims

Ok, so this is two things, but they go together like peanut butter and jelly. It all goes back to my days as a brand new private in the Army, as I was expected to always have something to write with and something to write on. You never know when you will need to take notes, write down an address for someone, or hash out an idea that you know you will forget later. You might argue that you can use your cell phone for these duties, and I would again remind you that cell phones aren’t always reliable. The more obscure uses for these items include using the paper in your notebook as tinder or using your pen as a self-defense tool.

For a pen, my personal preference is to use a solid aluminum “click” pen, which is made by many brands and can be found almost anywhere. No need to break the bank on your pen (you know you will lose it at some point anyway), but consider spending up to $20 for something that is of real quality. As far as your papyri is concerned, I’m a huge fan of the Moleskin pocket notebook. It’s durable and just the right size to carry on your person.

Finally, I am a big believer in posterity. A notebook that is used regularly and rigorously will automatically become a piece of history, even if it is just family history. Your kids will someday show your grandkids Grandpa or Grandma’s old “stuff,” which will include that beat up notebook. Seeing those GPS coordinates you jotted down or the name of that restaurant you really liked will give them a view into the person you were and where they came from. For me, that is priceless.