The Kalita Style UP pour-over coffee set features Kalita's patented wave design that reduces contact between the brewing space and the filter itself for a more balanced extraction and a flavorful, full-bodied cup of coffee every time. The design of the dripper and filter together help create a pool of water on top of the coffee bed that can help control agitation, helping maintain a uniform extraction without too much agitation (which could lead to over-extraction).