The stainless steel bottom plate of the group sits at a low position, under the water. This causes its temperature to be below the temperature of the water. Water passing the bottom on its way to the coffee grounds, should not lose any of its heat to the metal bottom. Therefore the dispersion block reaches up through the bottom plate, so the water directly enters the dispersion block. This block is made in a polymer plastic, a fully temperature-neutral material. As this block remains cool, the fats and oils in the coffee do not bake on, effectively keeping it clean for a long time. This block consists of two pieces offering a nicely divided dispersion of the water.
The group screen is hold in place by the surrounding rubber group gasket. To pull out the gasket with screen for controlling, cleaning or replacing, a special tool is provided with each machine in the Barista Kit. The rubber gasket ring sits against the bottom of the group. At the bottom of the group a small outward ridge is machined. This ridge is pushed into the rubber gasket each time the filter holder is locked into the group, as an extra sealing surface. The slight moving up of the gasket ring, because of the flexibility of the rubber, provides an ergonomically correct, soft comfortable feel for the barista. Full sealing is achieved without having to pull the filter holder firmly. The rubber group gasket is made in a heat resistant material that does not harden and go brittle. It remains flexible.
The group screen reaches up and sits against the bottom of the group. This makes it very strong. Together with the rubber gasket surrounding the screen, it is impossible for coffee grounds to ever reach the insides of the group. The supporting horizontal base of the screen is thick to resist deforming. This base is perforated and covered with a stainless steel membrane, not a woven mesh. This membrane provides a very even dispersion of the water during extraction. It also strongly filters the water sucked up when the pressure is discharged at the end of the shot. This again ensures a cleaner inside of the group.