About six years ago when I came back to flying RC, I bought a Goldberg Handi-Tote flightbox and it has served me really, really well. It's just gotten really old and scruffy looking, so I picked up a new one. Since I bought my original one, Great Planes has acquired Goldberg, so it's now called a Hobbico Ultra-Tote.
I could have gotten something different but this one actually works so well that I just wanted another one. This fieldbox was originally designed for fuel airplanes, but with a little tinkering I turned it into a good electric box.
As you can see, I keep my batteries on the end that was designed to hole a gallon fuel jug. I get the big plastic boxes at Harbor Freight, and they are perfect for holding five ot six of the 4s 2700 packs that I use in my 48" planes.
The other end is designed to hold a battery to run the fuel pump and glow driver, with the top open so you can put a power panel in there. I just leave it open and use it to store things like my prop reamer and big wire cutters, large Phillips screwdriver, reading glasses, and other tools that are too large to have clogging up the tool drawer on the front. It's generally filled with tools that I don't normally use at the field but can't afford to be without if I need them. You can also see I have my volt meter secured with Velcro to this end of the box.
I suppose eventually I will make a little door or a cover for the top of the hole, but right now it doesn't seem that important. I'll do it one day when i am, bored and looking for something to do.
On top, my Thunder Power 820CD or TP610C AC/DC charger (shown) will fit nicely. There's room for two 610Cs and a parts box underneath.
This particular parts box fits absolutely perfectly, and I can't find another one like it, so I sure hope nothing happens to it.
You hate to have your day end by something like a stripped servo, broken wheel or any other part that you probably have sitting at home, so it;s always good to take whatever spares you can fit in the box. You can see the kind of things I like to take with me. there are two servos in the Hi Tec box in case I strip one, and I like to tale an extra wheel. The entire Extreme Flight tail wheel assembly can be replaces at the field in about 40 seconds with just three screws, so I like to take a complete set up. I keep spare prop adapters and wing bolts, and the small square box is assorted nuts and bolts and such. I keep spare Velcro and Velcro strap in there too. I try to keep part in there that I or my friends might need. I also keep a spare LG assembly in the trunk of my car.
The tool drawer contains mostly everything I need to do maintenance and adjustments at the field, but thankfully electrics are so low maintenance that you don't really need a lot. On the left I keep my Allen drivers, nut drivers and screwdrivers, and on the right I keep anything that you can cut, poke, scratch or gouge yourself with, and the sharp end pointed toward the back of the drawer.
I like this particular box because it fits on the floor of the car in the back under the folded down rear seat, so it stays out of the way during transport. I had a flight box hit me during a car accident many years ago, so I want the damm thing locked away in a place where it can't get loose and smash my skull.
I try to put everything I need or might need in the box and I think this one does a good job for me. The only other item that I might need outside of transmitters is my charger power supply, but I just throw that on the floor beside the box.