Over the years, my first aid kit has morphed, getting bigger or smaller depending on my level of optimism. I’ve carried big kits with everything plus the kitchen sink, and minimalist kits consisting of a few aspirin and a roll of tape.
After decades of fluctuation, I’ve finally settled on a largish kit (at least by climber standards.) It has supplies in it that allow me to deal with some of the more common backcountry injuries: blisters, cuts, abrasions, bleeding, and pain. In addition to the first aid supplies, I have materials to start a fire and repair fabrics. A small leatherman tool and a small emergency flashlight provide some functionality for repairing and fixing things, cutting, and vision after dark.
I carry this kit with me pretty much any time I head into the backcountry. I’ve used everything in it at one time or another.
Here’s the contents of my current standard kit. Total weight is 13.3 ounces.