General description These 200-Pack Car Diffuser Sponge Refill Sticks are designed for use with ultrasonic humidifiers and diffusers. Each stick is absorbent and can be cut to fit your specific device, ensuring optimal performance. Technical specifications Size: 2.75 inches (length) x 0.31 inches (diameter) Material: Cotton Color: White Package Contents: 200 humidifier sticks Measurement allowed error: +/- 1-3 cm Usage Soak the filter stick completely before inserting it into the humidifier for better performance. Replace the filter every 3-4 months, or more frequently (every 3 to 6 days) if using essential oils regularly. Monitor the filter for blockages to prevent overheating and potential damage to the diffuser/humidifier.