Honeywell POPUP2400 16 in. x 27 1/8 in. x 5 7/8 in.Merv 11 Replacement Filter for Aprilaire, Space-Gard 16 in. x 27 1/8 in. x 5 7/8 in Replacement Filter Honeywell PopUP filters store flat and pop into shape for installation Merv 11 Dimensions (mm): 406 mm x 689 mm x 149 mm