Made of natural fabric, multi-layer mesh surface to maximize the output of humidifier moisture, but also better filter Limescale, the new upgraded material makes the filter more stable and filtering, can be used for a longer time.Including for WF813 RCM-832 RCM-832N,for PCWF813 PCWF-813 PCCM-832N PCCM- 840,for EQ-2119-UL-830, -832, AC-813, ACR-832, D13-C, -832, etc.Easy Installation,Remove the old filter in your humidifier, put this brand new humidifiers filters in its place and adjust it well. Normal use 1-3 months need to be replaced with distilled water or cold water to fill the tank, not hot water.Colour:WhiteMaterial:wood pulp paperPackage Contents:5 x WF813 HumidifierOnly the above package content, other products are not included.Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.