I first bought this bag in Kuwait. I used it for everything, ammo, extra mags, food, hygiene. After over a year on a rough deployment two other bags didn't last. this one has the ability to slide easily into a ruck or duffel even when they are already too full.
Now, I use it for my motorcycle tool kit. It fits perfectly into the bottom of my pannier and I am able to carry all the tools needed to perform maintenance or repair my adventure bike. The only thing that doesn't fit is my torque wrench.
The three compartments make it easy. For Roq straps and tie-downs I keep them in one side with my flex-a-funnel. In the center, I keep all my wrenches, sockets, adapters, screwdrivers(torx, hex, phillips, etc...), pliers etc. On the other side I keep some paper-towels, extra crush washers, screws, nuts, fuses, and wires (like gerbing connector or cell phone charge cord.
I now have three of them. one for Reserve Duty, the other two are on each of my bikes. No room for improvement on this one it suits my multiple purposes exactly.
http://www.specopsbrand.com/all-purpose-bag.html