[Cotton swab size] 0.32 inches (about 0.8 cm) (diameter) x 3.99 inches (about 10 cm) (length). The perfect filter rod of portable mini humidifier 500 ml. If necessary, you can cut it to match other humidifiers.[Advantages] The filter rod is made of high-quality fiber cotton. Strong water absorption to ensure normal operation of the humidifier. The perfect filter elements replacement, when the filter elements is used up, there is no need to worry about the service life of the humidifier.[Replacement] We recommend that customers replace the filter after 3 months of use (depending on the usage and water quality).[How to use] Please soak the cotton swab in water for 1 minute before use to make the swab completely wet.colour: whiteMaterial: fiber cottonsize: 8x8x100mmPackage Contents:20 x Humidifier filter stickOnly the above package content, other products are not included.Note: Light 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.