I carry a powerbank and various USB C adapters so if someone’s device dies I can help them out. It is a lot cheaper and smaller than carrying around seven different cables.
On top of that I carry Tylenol and bandages.
I used to carry a full first aid bag but kept forgetting to restock on supplies.
My keychain has a small knife on it, a small phillips and flathead screwdriver, a guitar pick, a handcuff key, a sim tool and a little metal pill holder! They’re all pretty handy to have! I also carry a regular pocket knife and a small flashlight clipped to my pocket
The SIM tool is a smart idea. I had one but kept bending the tip. I started carrying around a very small Allen key for it but it is slightly too think for some slots
I placed my flat sim tool between my phone and protective case so it’s always with my phone.
Smart thinking
I got a thing an Amazon where the tool folds inside of a little piece of leather so it doesn’t get bent up or stab me in the leg