It might depend on what they already have but...
Multi-Tool (Many will recommend a leatherman instead)
Glass Breaker (other brands/styles too)
There is also stuff like tools, ammo cans, mylar bags, oxygen absorbers, and some firearm accessories.
I got this last week as a just-in-case: https://smile.amazon.com/gp/product/B01N5L6UG9/ref=ppx_yo_dt_b_asin_title_o03_s00?ie=UTF8&psc=1
Has 2 external USB ports, a flashlight, and AM/FM/Weather radio; powered either by USB charging or, most importantly, by a hand crank on the back. Feels like this was a pretty timely purchase.
EDIT: Also has a solar panel for charging as well--in case your hand gets tired :)