The Rancilio Commercial Bottomless Portafilter is that next step in making a better tasting espresso. The naked portafilter is often used as a training tool. It is basically a portafilter (group handle) with the bottom cut out. It allows the operator to get a better look at the extraction so adjustments can be made if necessary, to improve coffee shots.
If any channelling in the puck occurs, you can expect to see exactly how that impacts your shot, making this an excellent tool for improving your espresso preparation technique. The Bottomless (Naked) Portafilter guarantees an irresistible display whilst extracting the perfect espresso shots.