Coffee Sensor Espresso Skateboard wood – DARK BROWN Coffee Stirrer or WDT tool.
It is a known and proved fact that WDT – short for Weiss Distribution Technique, offers even distribution of coffee inside the PF, so to to promote even flow and extractions and better espresso tastes in the coffee cup.
A lot of info can be read on the internet, for example on HB forum HERE – CLICK TO VIEW THE PRODUCT.