A long time ago, in a galaxy far, far away, I was Safety Officer in the office (about 40 or so employees) and thus in charge of the first aid kits which were quietly gathering dust in various nooks and crannies.. On occasion, they had been opened and their contents disturbed. About the only items that were used were bandaids and similar items used for boo-boos.

I restocked them and decided to place a band aid box next to, and outside the FAK so that thee contents would be in good order for more significant emergencies. This in turn led me to place about three or four band aids in my wallet, so that I could tend to the common incidents quickly, with no theatrics.

Doing SAR in that same galaxy, I developed a more heavy duty FAK more attuned to the situations we encountered, usually trauma as the result of falls - elastic bandages, leg splints, lots and lots of sterile dressings. Through time, I developed a smaller version of that kit for personal excursions. I have two or three such kits in handy locations around the house and car. My wife has even more, I found out the other day.

I would say that the most important component of any FAK is the training and experience of the person opening it. I would rather be treated by a trained person and no dedicated kit, than by a layperson with any kit you care to provide. The best situation is both an ample kit and a trained responder....