Winter vehicle survival kit

[EE_]

With winter here, it's time to check your vehicle survival kit.
What's the bare minimum you should carry in the event you get stranded?
If you're traveling into wilderness areas, you should have more items.
Add to the list if you like.

Must have items:

Extra clothing
gloves
snow boots
Knife
gun
road flares
lighter/matches
phone charger

Optional items:

shovel
food
first aid kit
flare gun
rain poncho