When I first bought this product I thought I was buying a box containing individual string sets. Not the case. I know I should probably read the packaging closer I'm discovered that it was in fact a bundle off strings on a spool. But soon my frustration at ordering the wrong thing, turned to "why didn't I ordered this years ago"
I find extremely helpful when changing guitar strings at home on multiple instruments, and even more hopeful when changing one I'll strings during gigs.
I carry a Steelcase for my effects pedals, leads and strings, and while it's a sizable box, it fits comfortably. With the color coding and choice of individual strings without having to open a fresh packet is great for changing strings on-the-fly.