Compatible with Waterdrop Reverse Osmosis Water Filtration System (WD-D6-B). 𝟔-𝐬𝐭𝐚𝐠𝐞 𝐜𝐨𝐦𝐩𝐨𝐬𝐢𝐭𝐞 𝐟𝐢𝐥𝐭𝐞𝐫&𝐞𝐟𝐟𝐞𝐜𝐭𝐢𝐯𝐞 𝐟𝐢𝐥𝐭𝐫𝐚𝐭𝐢𝐨𝐧: Waterdrop D6 RO system adopts advanced filtration technology.