Dri-Eaz * DefendAir * HEPA 500 HEPA Filter – F321 Part #: JAN-HVAC140 Designed to Fit: Dri-Eaz * DefendAir * HEPA 500 Material: HEPA Certified Filtration Efficiency 99.97% @ 0.3µm Case: 4 – 1 pks Dimensions: 2.2″ x 16″ x 19″ OEM: F321 You may also like… Read more Dri-Eaz * DefendAir * HEPA 500 Carbon Pre-filter – F397 Read more Karcher * Prochem * Triad * AFD Stage 2 pre-filter – 98409550 Read more Dri-Eaz * DefendAir * HEPA 500 Stage 2 Pre-filter – F271 , 13-00199 Read more Karcher * Prochem * Triad * AFD Stage 1 Pre-filter – 98409540 Read more Karcher * Prochem * Triad * AFD Carbon pre-filter – 86341690 Read more Dri-Eaz * DefendAir * HEPA 500 Stage 1 Pre-filter – F270 , 13-00202