NOTE: Some of Honeywell's F52D series models use a different size - # 190910, measuring 19-1/8 x 27-3/8 x 1/4. MEASURE YOUR EXISTING PRE-FILTER FIRST!
Approximately 19-1/2 x 26-3/8 x 1/4
Honeywell F52D1100; F52E1032
Other Manufacturer Part Numbers: SA549-19-1/2 x 26-3/8 x 1/4