Aprilaire Space Guard 201 Air Filter is the , OEM expandable accordion style filter designed specifically for the Aprilaire/Space-Gard Model 2200 and 2250 Air Cleaner. This factory filter arrives collapsed like an accordion and is easily expanded into a plastic frame within the air cleaner cabinet. It snaps securely into place with the existing pleat spacers, ensuring optimal performance. Clear assembly instructions are conveniently printed on the product carton, making installation straightforward and hassle-. Model Number: 201