Actual size is 16.63 x 26 x 4.13. Accumulair brand 17x26x4 Lennox X6666 replacement whole house air filters, specifically constructed to replace the original brand Lennox X6666 air filters. Completely constructed so no forming or combs needed. MERV graded to ASHRAE 52.2 test specs establishing function equal to the OEM Lennox X6666 filters. Notice: The sample filter pic shown is not to scale and is there to show configuration only. Trade names and Lennox X6666 identifier are included for air filter replacement identification purposes.
Shipping and Returns
- Our current lead times are 6-8 business days for standard filters (1"-6" thick sizes), and up to 10-14 business days for made-to-order filters (non-standard and 0.5" sizes). Delivery normally takes another 1-3 days depending on location.
- Shipping is FREE to the contiguous United States.
- 30-day 100% return policy.
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