QwenchPure Inline Showerhead Filter Replacement Cartridge - 100% KDF REPLACEMENT cartridge only for your QwenchPure showerhead filter. Keep your QwenchPure shower filter working its best with this 100% KDF Showerhead Filter replacement cartridge. For use inside the QwenchPure Inline Showerhead Filter. This is the replacement cartridge ONLY. Outer casing not included. To replace, just twist open your QwenchPure Filter and replace with a new QwenchPure Replacement Cartridge. Depending on water hardness in your area and buildup, it may be difficult to open the outer casing. You may consider trying to open it before ordering a replacement cartridge.