• Generalaire Part # GFI 4531
• Actual Size 20 3/4 x 19 3/4 x 4 15/16
• MERV 10 Rated
• Made by ReservePro Parts for Generalaire
• Replacement MAC TWENTY Filters
• Also for: S1 # S1-FM10202005, Source 1 # S1-MAC202005, Trion # 255649-103, Skuttle #448-3, Skuttle DB-0020-020, Air Bear Supreme 20x20, Generalaire MAC TWENTY
• Package 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 Rated 
• 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
• Made in Canada by FurnaceFilters.Ca
• 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 11 Rated
• 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

• Manufactured in Canada by FurnaceFilters.Ca
• Case of 3

• New MERV 13, Part # GF 4557, 20x25x5 Replacement Filter for Generalaire GF 4551 MERV 11 
• Actual/Exact Dimensions: 19 5/8" x 24 3/16" x 4 15/16" (with foam strips)
• Fits Generalaire MAC 2000, Trion Air Bear Supreme 2000, Skuttle DB0-0025-020, & Ultravation 90-007
• MERV 13 Rated
• Package of 3