This is for one filter cup. Cups are made from 6061 aluminum with a T6 heat rating (highest). They are black anodized finish to resist corrosion. Each cup is 3mm super-thick and have a very small center hole for drainage. Stainless Steel screens are included in each cup for capturing debris. OD = 37.7mm. All cups stack tightly with curvature into the next cup. Cup bottoms are flat inside and curved on the outside, which provide a super thick (7mm/over 1/4") thick bottom.
9" tubes hold 8 cups. 7" tubes hold 6 cups. 5" tubes hold 4 cups.