The Fellow Prismo is a replacement filter cap for the AeroPress, machined from stainless steel with a spring-loaded pressure valve that holds liquid in the chamber until sufficient downward force is applied — eliminating the pre-drip that standard AeroPress caps allow and enabling a more pressurized extraction. It ships with a reusable 150-micron etched metal filter, which passes more fine coffee particles and oils than paper, producing a heavier, fuller-bodied cup with visible texture closer to a stovetop moka than a clean filter brew. The pressure valve opens at approximately 0.75 bar — nowhere near the 9 bar of a commercial espresso machine, so calling the result “espresso” is technically generous, but it is genuinely richer and more concentrated than standard AeroPress output. It was designed by Fellow, a San Francisco-based company known for precise, industrially minimal coffee hardware, and it fits all AeroPress models including the newer Clear and the Go. For anyone already owning an AeroPress who wants espresso-adjacent results without a four-figure machine purchase, the Prismo is one of the most honest €30 compromises in specialty coffee.