BWT magnesium mineralized water. BWT Magnesium Mineralizer refill filter cartridges can be refilled multiple times. This not only saves you additional replacement filters and household waste but also allows you to be cost-conscious. The handling is incredibly simple: pry off the cartridge lid with a gentle push against the handle, dispose of the old granulate, clean the cartridge carefully, fill in new granulate, close the lid, let it soak - done! Features: - More flavor thanks to BWT magnesium technology - Suitable for all common filter systems with an oval shape - Capacity: up to 120 liters of water (per cartridge) or 4 weeks - Refillable - Cost-effective - Contents: 6 cartridges.