Usage Tips:COMPATIBILITY - The Humidifier Decalcification filter is compatible with all humidifiers with a water-filling diameter 1.5 inches. Compatible with for Top Fill Humidifiers, Dual 150, Classic 160, Classic 300S, Dual 200S, OasisMist 450S, OasisMist 1000S, and 600S humidifiers. FOCUS ON - The humidifier replacement filters offer soft and healthy mist by capturing minerals and irregularities from the water. The filter also keeps the humidifier clean and helps prevent white dust so that it keeps working at its best while producing the and cleanest mist possible. LAST LONGER - For optimum performance replace the humidifier decalcification filter after every 30-40 days. This package includes 8 pcs filters. Simply drop a universal demineralization for humidifier use into your humidifier.<br > <br > Please note: the physical slightly color difference or difference, does not affect the use, please do not mind, thank you! Colour:As Shown Material:plastic<br > <br > Package Contents: 8 * humidifier decalcification filter<br > <br > Only the above package content, other products are not included. Note: Light reflection 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.