AC-305 ELECTROSTATIC (WHITE) Filtering Power and Durability That Meets or Exceeds Original Equipment Repair or replace frame type air conditioner filters Rinses clean Traps most... ) Measure the width of the old filter. Cut the new filter to the same height. Mount replacement filter in place. Wash with mild detergent and rinse, as needed. Need help? Having... Instructions ( AC-323 & AC-337 ) Measure the width of the old filter. Cut the new filter to the same height. Mount replacement filter in place. AC-337: Fuzzy side towards room. AC-323...