This is a circulating water dispenser for dogs with a filtration function. I purchased it about a month ago, but didn't use it much, so I'm selling it. I washed everything after use and stored it in a dark place. It circulates continuously while the power is on, passing through the cartridge, so your dog can always drink clean water. There are a total of 20 cartridges. The manufacturer recommends replacing the M size cartridge every 20 days. The main unit and all accessories are included. Main Unit Manufacturer's Suggested Retail Price: 4,600 yen (excluding tax) Product Size: 14 x 23 x 13 (cm) Product Weight: 630g Cartridges: 20 water purification and softening cartridges Manufacturer's Suggested Retail Price: 1650 yen/each