What piece of gear would you tell a first time deployer to make sure to have?

Gold Bond body powder, a good multitool, Leatherman had just come out with the MUT (Military Utility Tool) on my last deployment so I got one it has tools for cleaning your weapon and adjusting the sights as well as a blade on the outside that you can open with your thumb without opening the tool. A folding chair with a back

Lot of interesting items. Times have changed. During my time it was a heavy duty plastic sealable bag for writing implements and paper, good quality knife, extra socks and gloves. We didn’t expect to much “down time” so only carry what you need because shanks mare can be tiring.

Camera and more books

DVD player

WOW things have changed! Most things were furnished for any deployment automation has ramped things up now so a lot of what we would purchase to take has been replaced buy a cell phone. Personal Hygiene items were automatic as were extra socks and underwear. Zip lock bags and just plastic bags before the zip locks were a must to keep things water proof and dust free. I had a leatherman when they first came out and always carried a p-38 still use both daily. Carried a fixed knife on my web gear and always carried 1 pair of socks 1 underwear and a T-shirt in a water proof bag of some kind (makes a great pillow). Always had a boy scout stick match container or Pill bottle with water proof matches put usually two sheets of news paper (PRE DRIED) in my underwear bag so I had quick fire starter. Small bottle of Mineral oil it has no smell, and a little goes a long way. A carton of Smokes in my back pack and always bought a refill when possible. Non sent Talc powder to help keep those spots dry. Bailing Twine black ( we could not find para cord like you can now), a watch, and one small radio with extra batteries and a ear plug. Flash lights were issued but when they came out with the smaller ones most everyone bought one it also went on you belt or web gear. A compass was always nice just in case so get the it works boy scout one inexpensive but usable. Dominos, and decks of cards Which could be gotten as a training aid, and a paper back book. A Sewing kit, I could almost a book of things but you get the Idea. We also packed three plastic tumble style cup. For coffee and many other uses. Good luck to all and as always Thank you for your service.

I found that a quilted sleeveless vest in the winter was the best piece of non-regulation equipment I had.

550 cord and riggers tape

multitool and a blow-up pillow....especially the pillow...and a good one at that...should have that rough canvas/rubber feel to it....loved mine....got it from a military surplus store years ago...still works...blows up AND folds FLAT !!!!! Best $15 I ever spent...

Baby wipes!!!

Take an unlocked cell phone that you can buy a chip and minutes to call home. You would be able to call a loved one when ever you can without waiting and standing in line to use a unit or MWR phone with limited minutes.