Brand: kaz Model: WF4 Quantity: Pack of 4 Type: Humidifier Filter kaz Evaporative Humidifier Filter, Pack of 4 + 2 extra, total 6 filters Part Number: WF4 This filter absorbs chlorine and bacteria from tap water. Although new and unopened, it has been stored for a long time, so it is old. Please refrain from purchasing if you are concerned about minor details. Due to shipping costs, the filters will be removed from the box and sent in a more compact form. Shipping will be via Yu-Pack or Rakuraku Mercari Bin, whichever is cheaper.