In general, the purpose is to get a meeting. So it needs to be short and exciting.
You very likely have little in the way of financials that's exciting. But, you (hopefully) have exciting points in one or more of the following:
1) user traction
2) Significantly better user experience / solving pain point in a large market - like dropbox doing a demo of their product for YC. And the more disruptive it is, the more proof you'll need that it's true
3) social proof
And then it all comes together in a concise story. You don't need anything more than that.
So let's say you have come up with a low-calorie bacon-alternative that's just as tasty. It could go like this:
"We have developed a low-calorie bacon that tastes like the real thing. It's made from a blend of plant materials, and in blind taste tests against bacon, 93% of respondents were unable to tell a difference. We even did a taste test on Oprah and she was unable to tell the difference.
Since appearing on Oprah a few weeks ago, we've sold 5,000 boxes through our website, but we're quickly falling behind demand and are seeking the right partner to grow with. We'd like to set up a meeting with you because of X & Y - are you free next Tuesday at noon?"
Who wouldn't take a meeting with that story?
So that's ideal hyperbolic case. But the closer you can get to that, and the more exciting you can make it, the better you'll be.
Note that in the above, I didn't explain why low-calorie bacon that tastes like real thing is amazing - it's self explanatory for lay person. But if your product satisfies a less obvious demand, it'd be helpful to include that.