It takes years and years of hypothesizing, tinkering and testing often to just take that information and start all over again. And if Bill Gates happens to be an investor in that that piece of equipment? You can bet it’s going to be a long and thorough process.

For the past four years, Global Good, a collaboration between the Gates Foundation and innovation lab Intellectual Ventures, has been working on the Passive Vaccine Storage Device, an insulated container that will help to keep vaccines fresh for more than a month at a time. Their hope is to extend the “cold chain,” the system that allows for vaccines to be transported from a manufacturer and delivered to the people who need them.