COMPATIBLE WITH BLUE PURE 211 plus AUTO: Genuine Blueair Replacement Pre-filter in Archipelago Sand (Pink) color for Blue Pure 211 plus Auto air purifiers | | FILTER LIFE EXTENSION: Colorful fabric pre-filter extends the life of the primary filter, catching large particles such as dust, lint, pollen and pet hair | | NO COMPARISON: Genuine Blueair pre-filters are specifi