The Panasonic FY-FD2217A fresh air purification filter is compatible with small-diameter heat exchange systems and provides air purification functionality. - Model Name: FY-FD2217A - Brand: Panasonic - Type: Fresh Air Purification Filter - Compatible Models: Small-diameter heat exchange systems I am selling these because I accidentally purchased the wrong model. One is opened but unused. The packing seal is peeling off. Please check the images before purchasing. One is unopened. If you would like to purchase one unopened filter, I will change the price to ¥3,000. Please comment. If you would like to purchase both, the price is ¥5,000 for the two. Thank you.