From Reinventing The Tea Bag: “The bags have paper arms on the sides that fold out in order to make them into a single-use filter. In essence, it is not that different from the function of a normal tea bag but now the tea inside is effectively loose because, before placing the tea in your cup, you tear off the top and then let the leaves float around in the open bag while it steeps. By opening the top, you are also able to pour the hot water directly onto the leaves without them scattering, which helps to make a fine beverage.”