I know where strats are kept

I have seen people wonder where are the stratagem beacons kept by the helldivers, since they are seemingly carrying around dozens of spheres that in no way can fit in their pockets.

I think I figured out: the stratagem beacons are inflatable.

They are stored as flat plastic disks, easy to carry and store. When needed, the helldiver activates them, and an heavy polymer dust swells as a foam inside the container, quickly making it change shape into the sphere that we all know and love.

It can't be air, because they wouldn't fly as far as they go if they were hollow, so they must be filled with something heavy.

The ingenuity of the ministry of science is truly inspiring.