Actual dimensions are 20.75 x 20.75 x 4.38. Accumulair brand: 21x21x4.5 Ruud PD540018 style whole house air filters, exactly engineered to be an alternative to the original brand Ruud PD540018 filters. Completely box-formed - no forming or combs needed. MERV classified to ASHRAE 52.2 test specs ensuring particulate filtration to the level of the original brand Ruud PD540018 filter. Note: The example filter image shown is not true to size and is there to show configuration purposes only. Brand names and Ruud PD540018 P/N used for filter substitution identification purposes.
Shipping and Returns
- Shipping is FREE to the contiguous United States.
- Our current lead times are 3-5 business days for stocked filters (standard 1"-5" thick sizes), up to 3 weeks for made-to-order filters (non-standard and 0.5" sizes).
Delivery normally takes another 1-3 days depending on location.
- 30-day 100% return policy.
Payment & Security
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