Trauma kits. Who has one and what do you carry in yours? I have one I made up myself. The bag is small, as pictured, and I bring it with me everywhere I go. I can also attach it to my range bag when going to the range.
I have a Gen 7 CAT tourniquet, 4" and 6" compression bandages (known as Israeli bandages), some combat (clotting) gauze, shears, medical tape, a small length of para cord, several pairs of medical gloves and a Sharpie marker. The marker is to note the time that the tourniquet was applied, if you can. There’s space on the tourniquet for that info. When I was in the Army, we were told to write it on the person’s forehead using their blood.
Most important is knowing how to use the items in the bag. There are classes available out there which I’d recommend you take to know how to really use the equipment. CPR certification is a good idea also. User tip: Have the tourniquet set up so you have minimal fumbling around in case you need to use it on yourself. One handed application is difficult at best.