Coffee filters/infusers, also known as Vietnamese coffee makers, provide coffee drinkers with the distinctive taste of filtered coffee in a single cup. These stainless steel coffee infusers from Thunder Group include a filter, inner pot, and lid designed to fit over a coffee cup. Simply place a puck of espresso in the pot, pour in hot water, and voilà—a freshly brewed cup of coffee is ready in about the same time as instant coffee.