[Filter Sticks Size] 0.31 (Diameter) x 2.75 (Length) inches. You can cut it to fit your diffuser/humidifier if needed. [Replacement] We advise customer to replace the filter after 3-4 months of use (depending on the usage and quality of the). [How to Use] To see better performance, we advise user to soak a filter stick completely and insert it into the humidifier. [Benefits] Extends the life of the diffuser: If the diffuser/humidifier is always fully blocked or half blocked, it will become hot and break easily, we strongly recommend you to use essential oil solubility in the oil and the oil. Usually 1-2 weeks, replace the filter or easily connect the machine. If you use essential oils regularly, you need to replace them every 3-6 days. Size: 7cm in length and 0.8cm in diameter Material: cotton swab Color: white Package Contents: 250 x Humidifier Sticks Cotton Filter Sticks (excluding other display items) Only the above package content, other products are not included. Note: Light