A short pitch has one purpose, to set up a future meeting. When you remove the pressure of thinking that you need to sell in a short pitch,
the pitch is usually much more effective.
Need - The problem your product or service solves. Every idea for a new product or service came about from a problem or pain that people experience. This is the need that is solved.
Approach - This is the how. How does your product or solution work to solve the need/problem/pain that your ideal customer is facing? Technical solutions often have trouble here. Even if your solution is very based in technology, explaining how it solves the problem doesn't need to be very technical. Use language that a 10 year old can understand and you'll be on the right path.
Benefits - Often we are given a list of features when we hear about a product or service. Features are great but the benefits these features provide are WHY people will become interested. Do you use the fastest technology? Great but time saving is the benefit! Focus on these and people will know exactly WHY they want to meet further with you.
Competition - Why are you the preferred solution to this persons need or problem compared to others? Are you the first one solving this problem? That may be so but, doing nothing is still your competition.