The Swissgold filter system was developed as an alternative to the paper filter to get the best tasting coffee. Due to its absorbent properties paper removes all fats from the liquid being filtered, so although a paper filter retains all the coffee grounds it also retains all the brewing colloids (flavour carriers in the coffee). The stainless steel filter is inert so prevents any tainting of the taste of the coffee. This Swissgold KF300 filter is Biphenyl free To make your coffee simply place the one cup filter on top of your mug, put the appropriate number of scoops of medium ground coffee into the gold filter, insert the perforated insert and pour just-off-the-boil water into the filter. The perforated insert means that the water does not come into contact with the coffee in only one place but is evenly distributed over the coffee for maximum flavour extraction. Height100mm Diameter90mm (base) Dishwasher Safe