I carry a small "get-home" bag in my truck. I have a couple bottles of water, an orange tarp with a silver reflective side (to use as an emergency thermal blanket if needed), a Gerber Strongarm fixed blade knife, a SOG folder (also always have a Spyderco folder in my pocker), an extra mag for my ccw pistol, a 120 lumen Streamlight flashlight with extra batteries, small first aid kit with bandages and band aids, a change of socks, and a couple trail mix bars. I am usually wearing some comfortable, strong boots or at least have them in the truck with me.

I always have a small tool set and jumper cables in my truck in addition to the bag.

Here is the bag I have. It is rather small, so you have to be selective on gear and creative in packing it. https://yukon-outfitters.com/products/explorer-side-pack?variant=1202030173

Here is my fixed blade: https://www.amazon.com/dp/B0108CK1Q2/ref=cm_sw_r_cp_awdb_8ZQzybBP3QERT

Here is the tarp: https://www.amazon.com/Ultimate-Survival-Base-Hex-Tarp/dp/B00G2TXJ7O

Edited for words