 solutions to remove microplastics from the water are not very effective. They're too expensive, kind of inefficient, or sometimes they add in harmful chemicals, which might be bad for humans to consume. So we wanted to explore a more non-invasive method to removing microplastics from water. So not having to add in anything and we kind of found ultrasound as an option. You're using an ultrasound filtration system. Can you explain that to me?