Hario Mugen is a rib-less v60 coffee brewer. It has a relatively smooth wall to minimize water bypass. The idea is to create a one-pour coffee brewer. I think it works great most of the time. Perfect when you just want to make a simple cup of coffee. My issue is that sometimes placing the … Continue reading 3D printed v60 paper filter folding tool (negotiator) for Hario Mugen