Espresso & Coffee

Knock Box

A padded bar to knock the spent puck out

Maintain stage

Specification
What it does	Gives you a soft, fixed edge to knock the puck out against, so the force goes into the basket rim rather than your wrist or the counter.
The bar	Rubber or silicone over a rigid core. A hard plastic bar transmits the shock straight into the handle and eventually loosens the basket.
Size	Wide enough for a 58 mm basket with room to spare, and heavy enough that it does not slide on the counter.
Lining	A removable inner bin is far easier to empty and wash than a one-piece box.
Hygiene	Spent pucks are wet and sugary. A box that is not emptied daily starts to smell.
Placement	Next to the machine, at the height of the group head, so you are not carrying a wet basket across the counter.

Overview

A small bin with a shock-absorbing bar across the rim. You strike the portafilter against it and the puck drops out without damaging the basket or the handle.

Espresso

Safety

Knock against the bar, not the counter or the bin rim — an unsupported strike bends the portafilter lugs and can crack a ceramic counter.

Technical parameters

At a glance
Bar	Rubber or silicone over a rigid core
Capacity	10–20 pucks between empties
Fit	58 mm basket and larger
Liner	Removable inner bin preferred
Cleaning	Empty daily; wash weekly

What actually goes wrong

Hold the portafilter by the handle and strike with the basket rim square to the bar.
If the puck sticks, the dose was probably too low or the basket too dry.
Line the bin with a compostable bag if you compost the grounds.

What it has to match up with

Portafilter of any size
A spot beside the machine

This guide is an independent educational reference. It is not a substitute for the instructions supplied with your own equipment, and nothing here is sold, sponsored or endorsed by any brand.