Battle Board
Getting one of these made my life so much better. You can organize your whole call for fire kit into one compact package. I would recommend getting one of the binder ring inserts to go with this so you can insert your own custom laminated templates. The battleboard company makes many sizes, but I know amazon has some other (maybe cheaper) options. I found the battleboard (company) ones to be of super high quality. The one I used (medium) fit well in a dump or admin pouch. Your team will probably have some custom templates for CFF sheets they use. Just scan those (add some of your own), print them, and laminate. I much prefer to make my own kit than use what gets passed down in the team.
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Laminator
This will allow you to print and weatherproof pretty much anything. I made my own call for fire playbooks and other sheets I knew I would want to reference during missions. These are also great for making yourself a more valuable team member. Help your buddies out by offering to print and laminate for them. When new to a team, finding ways to contribute is very important. It also just sets you up for success.
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Rite in the Rain Notebooks
I know pretty much everyone in or associated with the military knows about these. I would definitely buy multiple of these notebooks. I usually kept one in the back of my battle board and one in my back/cargo pocket. These are invaluable as being a good FO requires A LOT of documentation. Track your missions, do quick terrain sketches (do full ones on laminated sheets), and when the range goes cold, record admin items. All of these things will make you a better observer and a general asset to your team.
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Red Lens Headlamp
Night ops can be made so much more successful by having a good red light. Get one of these and put it in your kit for when it rolls around to to night missions. Its best if you get a good headlamp (hands free) with a strong red lens and the ability to switch to white when doing general admin tasks. I would also recommend getting a small backup red lens light (like a keychain light) for when you need to do quick tasks and don't want to pull out your headlamp. Redundancy is key in the field. YOU WILL LOSE GEAR and you don't want to be caught searching when the gunline is waiting on you for a mission or the target is temporary.
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Protractor
These are essential for doing your job. YOU WILL LOSE MANY. Get multiple backups. I prefer the circular ones, but maybe get a combo pack first so you can see what you like. Also if you have a ton of these, you can lend them out to teamates in times of need. Make yourself an asset to the team by being prepared. I would also say that you should tether these things to yor battle board. Down below, I show some stretchy cord that can be used for this purpose.
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Map Pens
There's not too much to say for this. Get a ton! I think black is the best just because of visibility when using redlight. The combo color packs just seem like a waste to me. I also make sure to get the super fine ones to keep my map work tidy.
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Tether Cord
This stuff would be great for tying everything down. OPs tend to get very windy and if you can secure everything to your battleboard you will be in a much better place. Use a small pin or something to punch little holes in items (like protractors) and tie them into your board. You absolutely don't want something to blow/roll down the hill halfway through a fire misssion. These cords also have a little stretch to make them easier to use. When you tie the knot, I would take a lighter to it to make sure it doesn't come undone.
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Correction Pen
I like to have multiple quick ways to erase stuff on my maps or laminated sheets. These are good to make small corrections or to get an area ready to be cleared with a magic eraser (see below). I would recommend getting multiple of these as they tend to get lost or run out of fluid.
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Magic Eraser
Great for removing all the map pen markings. Use by themselves or with the correction pens. I would break each one into thirds and put them in my pockets or in the back of the battle board. Like mentioned above, you would probably also want to tether these to your battle board. They are super light and blow away very easily.
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Pistol Tether
These things are great for securing bigger items to your body. Don't just think pistols. You can use them to secure NVGs or other optics. This just clears up your mind to worry about one less thing in the field. They attatch to your belt and then from there, pretty much anything on the other end. If you are worried about it, you can even use it to attatch your battle board to your body. Make it so you (as an FO) can get up and move fast without losing a thing.
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Chair
When the range goes cold, these things make your life so much better in the field. You can find cheaper options, but this is the one I use. It is durable and packs down very small. Everyone will steal your chair, but once you get a little seniority, shove them out of it to assert dominance. Also, protect it against your massive buddies (think steriod use). I haven't tested it against that boss, but just play it safe. I've had others break.
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Multi-Tool
You will find yourself using this so often just in general in the field. I cannot express how valuable a good multi-tool is. Once again, think about tethering this to your body.
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Hand Warmers
These will make your life so much better during late night ops or early morning check rounds. Get them in bulk and scatter them through your various packs. Once again, this is a great way to be a team player. Get extras to share with your buddies. Build some comraderie. Think of them in much the same way as cigarettes.
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Shemagh
I love these things. They are very versatile and will really keep you comfortable in a variety of environments. They are great sun protections and keep the dust out. If you can make it work with your command or you are far enough out, break one of these out and improve your life. Get the colors that match your environment.
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