Tip to avoid panic about valves damage

I had the experience of being out using my portable E tanks and tank fell and broke the regular adjustment know. I was lucky and was in my truck and had pliers to adjust my Flo level.
I was refuse by supplier for a extra valve in case it happened again. So while at a auction I saw a set of E tanks with the same valve. Got them for 2 dollars. Tried the valve and it worked and that was a emergency back up for me. It did come in handy because I broke another valve and replace it than. What a difference in not having a panic attack over the anxiety of worrying. I also picked up a few extra bottle carriers, more bottles and more valves. Sense the name of company of Healthcare company on bottles were the same I had them filled so I could put those bottles either at friend's house I visi a lot, my garage even under my back deck. I do run the tank out of oxygen by not thinking about the level left and find myself out and there next by is a replacement tank. That's not only reason. I was getting lumber at lowes and by time I got to truck the tank was empty. I did grab a extra tank before leaving house but for some reason this does happen to many time that when put valve on extra tank the tank connection to valve leaked big time. Change rubber gasket and it didn't work. Luckily I had one of these extra bottle in my truck tool box.
Note here I don't know if I'm supposed to get these extra tanks, valves and use them in this way. But sense I can't them to help me prepare for these things to when they happen I found a way to solve the problem.
Harry