Invacare Polaris EX CPAP with SoftX ISP3000 Operator's Manual page 37

NOTE: Dry the air filter on a dish rack or squeeze between paper
towels.
3. Gently, but firmly, insert the dry air filter into the air filter
receptacle at the rear of the unit by tucking the edges into
place.
NOTE: The air filter is subject to normal wear and tear and should
be replaced every six (6) months. Check periodically for excessive
wear and replace as necessary.
Part No 1110559
SECTION 9—MAINTENANCE
37 Invacare® Polaris™EX™