• Compatible with 1.6 L, 2.0 L, 2.4 L, and 2.5 L pet fountains. • Filtration system composed of ion exchange resin and coconut shell activated carbon. • Helps absorb heavy metals and soften tap water to prevent urinary diseases. • Set of 12 replacement filters that improve water filtration efficiency. • Design compatible with models with a slot diameter between 12.5 and 13 cm. • Easy installation by placing the raised side up and the flat side down. • It is recommended to rinse the filter well with water before use and replace it every 2 to 4 weeks.