My "BOB", sitting about five feet away as I type this, is strongly influenced by the backpacks I used doing fairly extensive and frequent SAR many moons ago. Sometimes the necessary response was leisurely and all too often, immediate.

The bag was therefore packed with basics, along with fairly elaborate EMT items and enough gear to see me through about two nights out in the hills. Usually there were a few items of technical climbing gear.

The contents of my bag are considerably less complex these days, since I now only need to contend with the benign SoCal climate. But I can easily get ready for a typical day trip and make quick forays to the Channel Islands.

This set up was very useful when we had to evacuate a couple of years ago. The pack was tossed in the car,along with our caged cat,a bit more water, sleeping bag, emergency money supply and other odds and ends and we left at 2 AM. most of this stuff was not really used, but we lucked out, staying at no expense in a decent motel. I was still glad I had my basic gear, essentially the ten or so essentials, as well as other basic gear (suitable clothes for the climate and for comfortable sleeping).

Generally,your gear needs to be tweeked for different seasons and situations. This was especially true in southern Arizona, where you could be on snowshoes one week, and conducting swift water rescue the next.