This is the espresso machine basket developed by VST. 

Each basket has been designed and created in such a way that it guarantees a size, distribution and shape of holes perfectly suited to extract the chosen amount of coffee. 

In essence, this means that you can now grind finely enough to properly extract your dose of coffee, while still maintaining a desirable flow rate and brew time of approximately 25-30 seconds.

There is more information here.

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