Your tactical kit (often called a Bug-Out Bag or Go Bag, for short) should include everything you need to survive during and after an emergency. The question really isn't what you need in your kit, though. It's, "How prepared do you want to be?"
Putting together a tactical kit is about survival, not comfort. Start with the basics:
These basic tactical accessories don't take up a lot of room in a Go Bag, but they're the bare minimum you need. They can get you through Day Zero of an emergency, but you'll need to branch out if you're looking at longer-term survival and preparedness.
A small or mid-sized Go Bag that you'd stash in your car or store with your emergency supplies should include doubles of all your basic essentials. (You started with one fire starter – now add another. You get the picture.)
A better-than-basic tactical kit that can sustain you during the days beyond an emergency should also include:
If you're preparing for a specific emergency, you'll likely have more to add. Some of your gear might be environmentally dependent, too, like a cooling bandana or a balaclava.
Building a fully comprehensive Bug-Out Bag requires more gear, and it'll be heavier to carry – both important considerations. But a full-scale tactical kit will take you farther and help you survive longer than a smaller kit will.
A full-scale survival bag also includes "mission-dependent" items. If you're prepping for more than one scenario, you might prefer packing a handful of smaller bags that can fit inside of your Go Bag. You could also attach mission-specific MOLLE accessories to the outside of your pack for modular flexibility in a range of situations.
In addition to mission-specific or environmental equipment and all the supplies above, your full-scale Go Bag needs:
This beginner's guide to making your own tactical kit can help get you started. But remember – always evaluate and reevaluate your gear list based on the specific season and emergency you're preparing for.