[Filter Sticks Size] 0.31 inch (Diameter) x 2.75 inches (Length). You can cut them to fit your diffuser or humidifier if needed. [Replacement] Replace the filter every 3–4 months, depending on usage frequency and water quality. [How to Use] For optimal performance, fully soak the filter stick in water before inserting it into the humidifier. [Advantages] Helps extend the lifespan of your diffuser or humidifier. Regular use of clean water and water-soluble essential oils is recommended to prevent clogging and overheating. Replace the filter every 1–2 weeks under normal use. If using essential oils regularly, replace every 3–6 days. Size: 7 cm (Length) x 0.8 cm (Diameter) Material: Cotton Color: White Package Contents: 50 × Humidifier Cotton Filter Sticks (excludes other display items) Note: Color may vary slightly due to screen settings. Measurement tolerance: ±1–3 cm.