You are buying a pack of 10 compatible filter pads to fit the Eheim Ecco filter range. These pads are suitable for the Eheim Ecco 2232/2234/2236 and ecco pro 130/200/300 range of filters. These pads measure approx. 147mm in diameter and are around 20-25mm thick. These are not original pads, but compatibles which are made from the same material, and serve the same purpose as the Eheim originals.