Trion/Air Bear 4531 Aftermarket 20x20x5. Actual Size 20 3/4" x 19 3/4" x 4 15/16" MERV 10. Case of 3.

Aftermarket 20 x 20 x 5 Pleated Filters
Actual Size 20 3/4" x 19 3/4" x 4 15/16"
MERV 10 Rating Also fits:
S1 # S1-FM10202005, Source 1 # S1-MAC202005, Trion # 255649-103, Skuttle #448-3, Skuttle DB-0020-020, Air Bear Supreme 20x20, Generalaire MAC TWENTY, Generalaire #4531
Case of 3
Mfg in Canada