| 1. Take the filter out of the frame. Release the frame bolt first and take out the filter from the frame. |  | 2. Change the filter. First take the used filterout. Then put the new filter into the frame as shownon the photo by pushing it hardand set it for the center hol. |  | 3. Be careful not to make a gap. Set the filter tight to the frame. Do not try it a once but put it by step by step carefully. Try not to make any wrinkle. |  | 4. Finally set the bolt. Put the filter in the frame tightly and set the bolt firmly. Make sure again there is no gap between the filter and the frame. |