ZVac Rainbow Rexair E2 Series Washable & Reusable Exhaust HEPA Filter; Similar to Part# R12179 and R12647B; By This ZVac Filter Fits Rainbow Vacuum Rexair Vacuum Cleaner E2 Series Exhaust HEPA Filter Replaces Rainbow Rexair Vacuum Part# R12179 and R12647B This filter is equipped with the square opening for all machines with a serial number between #9280000 and #1000000 If you have allergies, this filter is absolutely essential for Allergy Sufferers! 99.97% Allergen Filtration Made by ZVac