We use only carefully selected premium virgin pulp. Because it is unbleached, it is naturally brown filter paper that retains the pulp color. Melita was born in Germany, a state of the art environmental advancement. [Aroma Hole] Rich coffee aroma: The "aroma hole" is a fine hole on the entire paper to extract the deep aroma and delicious. (Safe Double Tool) For ease of use, we have double the joint. The strength after getting wet. Of course, there is no glue.