LIGHT ROAST FILTER For Aroma & Clean Cup - Thickness-1: Thickness 0.15 mm - Density: High - One-Side Crepe (No crepe on inside and crepe on outside) There is no crepe inside paper, so the inside surface area is small. Coffee fine powders attach within this small area, so little water path is left then water is building up inside paper filter. By building up water, plenty of aroma comes out. Further more, thanks to the outside crepe, the coffee liquid came outside flows smoothly. Because its paper density is high, almost all fine powder is removed perfectly. You can get a clean cup of coffee.