Knock box

A container with a soft rubber-coated bar across the top, used to bang spent coffee pucks out of the portafilter after a shot. Sits next to the machine; built-in versions are integrated under the bench in commercial setups.

Why it matters — You need somewhere to put the puck. Knocking against the bin damages the portafilter, dents the bench, and looks unprofessional. A knock box absorbs the impact and contains the grounds cleanly.

Good to know

• The bar is consumable — replaceable on most boxes when the rubber softens.
• Empty daily for home use, more often in cafés. Wet coffee grounds start to smell and grow mould within a day or two.

Related: Knock Boxes