In practice, I find that my car kit is split into several "kits."

Mechanical kit: the usual suspects that keep a car running, deal with minor breakdowns, keep it visible in a pickle, and facilitate a dig-out or pull-out from a ditch or snow bank.

People kit: keeps people warm, hydrated, first-aided, crudely fed, and well-communicated with the outside world. Includes a few spares for people also stranded but practically naked except for a smart phone.

Deep 05H!T kit: this supplements the kits above; some is readily accessible and some is packed in around the spare tire; typically includes a short, indestructible axe, a surplus SWAK-knife or multitool, vise-grip, saw, a decent sized pot, firemaking gear, and other things a dayhiker would normally carry.

As well: I try to have a selection of key items in a daypack that I can toss in the trunk of someone else's car (which for various reasons ends up as the transport of choice). I always get a fair bit of chaff about this, but I pay little heed, since nobody turns down the gear when they need it, so they're just blowing smoke.

Work out what goes in the kit first, if you can. That will inform the size of the bag you need.

For me, backpacks work better than shoulder bags for weight of any significance and walks of over about half a mile.

While you won't want to store water long-term in a hydration pack, having the option to bring water with you is essential. Being able to drink on the move can be handy. I've done well waiting for Camelbak sales.

I'd avoid anything tactical looking, especially if you're in an urban area. You may find it useful to be able to blend in.

My kit serves several purposes for me and is customized to my experience, training, and habits. If you're like me, you'll be tinkering with the contents of your kit regularly. This will change the bag or bags that you use over time.

Bingley,

Like others I separate things. There is a tool kit (things for the car) in a tool bag. There is a 72 hour kit in a backpack. There is extra food and water in a small duffel bag that can be strapped on top of the 72 hour backpack, but is used at the car significantly more often. There is also my most used kit, a spare set of clothing, from the inside out, with toiletries for an overnight or when I get dirty or wet. It is in an old canvas breif case (except for the boots). If I needed to leave the car in a hurry, 15 seconds would have it together to leave. Most of the time I just need a bottle of water for someone who is dehydrated, a snack for someone who forgot breakfast or a clean shirt because I spilled my lunch.

Respectfully,

Jerry

Ditto.

And of course your vehicle influences what you can carry. I carry a lot more in my Element than I ever did in my Miatas.

I have one good-sized day pack (1700 cu in) in the car and a few smaller packs in there. You may not be alone in the car when an emergency occurs.

Your vehicle will also influence how you store and carry your kits. Don't just assume that putting everything in one or two bags is the best thing. In my case I have a Subaru Forester, and underneath the back removable flooring, there are a wealth of "nooks and crannies" built into the covering (removable) over the spare tire. There is more room around the spare itself.

Thus, I carry tools for the car, a FAK, various bug out gear, and a couple of collapsed back packs. All of this remains out of sight (no tempting bags visible from outside) and leaves the rest of the space in the car open for other things.

A Tantonka Barrel Roller

Favorite bag? Get a medium size (3500 cu in+/-) to carry items you would wish to take with you if you ever have to leave the car. As others have commented, many components can be distributed in various spots around the car.

Bags are good for some things, not so good for others. Some parts of my truck kit are in hard plastic crates, my winter supplement (extra wool clothes and stuff) is in a couple large nylon duffel bags.

Any EDC items would be in addition to what is in the truck. The idea being that if I can get to the truck nekkid and hungry, I have everything I need.

I've started putting together my own car kit, referencing the various threads and other internet sources. I have some stupid questions, and I figure I'd rather ask them now than pay for ignorance later.

1. Almost everyone includes jumper cables in their car kit. How useful are these actually? It seems to me that in town I can probably get towing service in the time it takes to find another car/driver to help jump the car. (Am I overestimating roadside service?) Away from town, it would be a long wait before someone stops to help. Wouldn't a standalone battery jumpstart system work better? Or would that be an overkill? Also, how likely is a car battery to fail? I have ever seen this in movies. (Of course, I don't think I actually know anyone who carries a kit in their car, much less go through the trouble of putting together one's own kit, so maybe this is all a preparation exercise.)

2. Some people have both towing ropes and chains in the kit. On another forum I found people advising against using chains or ropes with metal attachments. If they snap in half while towing, the metal bits could do serious damage to the car body and anyone standing in the way. So why do some people have both in their kit? What are the chains used for?

3. What do you do with tea lights? I will include a flashlight and matches. But it seems that some people include this ancient technology for reasons beyond my ken.

Thanks for the help!

Da Bing

Car batteries fail when you least expect them to; they are really fond of Murphy's Law. Without jumpers, you are SOL. With them, you have options.. Jumpers are not just for you - you might run into someone to whom you can give a jump.

I just bought my first standalone battery system. We'll see...

I like a good sturdy tow strap, not a rope. Whatever you use, keep people out of the path of the appliance. I once sacrificed a good climbing rope to tow some guy's RV and we managed to snap it. It was a very spectacular event. With the forces involved, any rope or strap breaking will inflict serious injury to anyone in the way, with or without metal.

Tow chains are very stiff, with no give or elasticity. I have found several times that the elasticity in nylon is beneficial in getting the stuck vessel to more or less "pop out." In a serious situation, you are likely to need both.