Why is it important to remove the slack out of a tourniquet before you start tightening? There is an inner band that runs all the way through, up through the windlass, and then runs the entire length of the tourniquet. If I take this tourniquet and I cut it, what you'll see here is that that inner band runs on the inside of the tourniquet.

As you tighten up this windlass, it pulls the band through the tourniquet, and that gives it a full 360 degrees of circumferential pressure. Let's take a look at what happens when you apply a tourniquet without enough tension taken out of it initially. And you can see it's loose in here. I can fit a few fingers under.

And so as I start to turn, I'm getting most of this slack taken up and I'm still not tight enough. I'm getting less mechanical advantage. I'm squeezed together here on these plates. So it's just not as efficient and I'm not going to get that same amount of tension as when I start with a really tight tourniquet.