The "Oh Sh*t kit"
Some of the links on this page go to HowNot2.com. These are not affiliate marketing links. They are provided as a convenience to you. Your purchase supports the awesome gear testing YouTube channel HowNOT2.
Having a few basic tools to ascend a rope, set up a mechanical advantage haul system, or cut a rope / webbing is a great starting point for just about any sort of rescue scenario.
There are many items you could put in a kit like this. A frugal start is a couple of prusik loops and spare carabiners. But, having some dedicated gear offers greater efficiency and more options. Combine this rescue gear with a couple of 60 or 120 cm slings, or a cordelette, and you can do all kinds of rescue trickery!
For alpine climbing, here's what I usually carry:
Petzl Nano Traxion progress capture pulley
Petzl Tibloc rope grab
Sterling friction hitch (Hollowblock, or shown here, 6 mm autoblock cord)
Tiny hardware store cheapo lockblade knife, with tape wrapped around it to prevent it from opening accidentally, and a short clip-in loop attached. If you want a better knife, check out the Trango Piranha or the Petzl Spatha
All conveniently racked on an oval locker
The knife is used to remove sun-bleached ancient crusty webbing from rap anchors (hopefully replaced with new material by you), to cut a cordelette for rap anchor material, and if needed, to cut away something under tension in some sort of awful rescue rescue scenario where it might be your least-worst option. (See the classic Joe Simpson book “Touching the Void” for an epic story about this very thing.)