As a former Marine, I carried a few different knives. My favorite fixed blade for the money is the Gerber Strongarm, but there are better knives if you're willing to pony up the money. Here are some combat knives you'll see guys carrying. https://www.marineapproved.com/best-combat-knives-review/ Someone also said that multitools are carried and that is correct. Leatherman Wave Plus is really nice and Gerber MP600 was a required item on the Ranger training gear list, but I'm not sure if it still is.