[Compatibility]Rplacement filters & pre-filter sponges set, completely for 84oz/2, blue and gray automated cat water fountain. [ Triple Filtration System]Cat water fountain filters come with 3 layer filtration system, high density cotton non-woven materials can fliter hairs and residue, maintain water clean; Activated carbon can get rid of chlorine and odor, purify and freshen water; Ion replace resin can filter heavy metals and improve the taste, can hold water clean, brand new and engaging all day, and decrease the risk of urinary tract infections. [Pre-Filter Sponges ]High density pre-filter sponge round the pump, can bigger filter out impurities, preventing them from moving into water pump, it is going to help increase the pump life. [Replace Filter Regularly]Suggest replacing the filter each 2 to four weeks and update the sponge every 4 to 8 weeks; Please change it extra usally if have multiple pets. [Warm Tips]Before changing the filter, please soak the filter out in water for two minutes after which rinse it very well beneath operating water, that will prevent carbon filth from shedding into water, hold water clean. Filters for 84oz/2 Pet Fountain Colour:As Shown Material:Polyester Package Contents: 4*Replacement Filters 4*Pre-filter Sponges Only the above kit content, different merchandise aren't included. Note: Light reflection and diversified reveals may cause the colour of the thing in the photograph a chunk assorted from the genuine thing. The dimension allowed error is +/- 1-3cm.