The Espresso Filter basket is what filters out the grounds from your coffee to give you a rich and creamy shot of espresso. There are many different styles of filter baskets but the two types you should know are pressurised, non-pressurized, and blind. Pressurized baskets have a standard mesh base and an additional wall barrier with one hole which creates additional pressure within the basket and helps to compensate for any errors during the extraction. Non-pressurized baskets are the traditional basket style and have a single filter which gives you great control in extraction and is the favorite for coffee enthusiasts. Blind bakers have no holes and thus no filter, they block the water flow completely and are only used for black-flushing the espresso machine during cleaning.