Filter Hut's 21x21x5 Rheem/Ruud (PD540018) compatible filters are specifically engineered to substitue for the name brand Rheem/Ruud 21x21x5 air filters. Filter Hut filters are MERV graded to ASHRAE 52.2 test standards ensuring that our air filters will perform as good or better than the name brand part number (PD540018) filters. Our air filters can be selected with Odor Ban odor filtering carbon-inlayed media. *Name brands are shown for air filter substitution identification purposes only.
- 21 x 21 x 4. 5 nominal size.
- 20-3/4 x 20-3/4 x 4-3/8 actual size.
- Replaces Rheem/Ruud brand 21x21x5 part number: PD540018.
- Quality Filters Envaero brand.
- Engineered to replace the name brand filter.
- Preassembled in frame for ease of installation. (Non-expandable, no end caps needed, etc.)
MERV graded to ASHRAE ratings.
- Option of Odor Ban odor filtrating carbon material.
- 2 air filters per case.