We humidifier filter is made of natural fabric with a multi-layer mesh surface to maximize humidifier moisture output and effectively filter limescale. The upgraded material enhances stability and filtration efficiency, allowing for extended use. Compatible with Relion WF813, RCM-832, RCM-832N, PCWF813, PCWF-813, PCCM-832N, PCCM-840, EQ-2119-UL, SH100, SH200, and Robitussin humidifier models -830, -832, AC-813, ACR-832, D13-C, etc. Easy installation: Remove the old filter and replace it with this new filter. Adjust properly for optimal performance. Replace every 13 months depending on usage. Use only distilled or cold water in the tankdo not use hot water. Color: White Material: Wood pulp paper Package Contents: 10 x Filter Note: Light reflection and display differences may cause slight color variations between the image and the actual item. Measurement may vary by 13 cm.