✓ 2-STAGE FILTRATION SYSTEM FOR ADVANCED AIR PURIFICATION ✓ CAPABLE OF FILTERING/SCRUBBING/CLEANING UP TO 3300 CFM OF FRESH AIR ✓ USES AN EFFICIENT MIX OF AIRFLOW AND FILTRATION TO CREATE CLEANER AIR THIS GLOBAL INDUSTRIAL COMMERCIAL AIR SCRUBBER & NEGATIVE AIR MACHINE IS YOUR SOLUTION TO HEAVY-DUTY AIR PURIFICATION. FEATURING ADVANCED HEPA FILTRATION TECHNOLOGY, THIS 2-STAGE FILTRATION SYSTEM DELIVERS ADVANCED LEVELS OF AIR PURIFICATION FOR WAREHOUSES, FACTORIES, AND OTHER LARGE SPACES. BUILT TO PERFORM IN COMMERCIAL, INDUSTRIAL, AND RUGGED ENVIRONMENTS, THIS UNIT PRODUCES 3300 CFM. WHEN PLACED AS A STAND-ALONE UNIT, THIS VERSATILE MACHINE ACTS AS AN AIR PURIFIER. WHEN ATTACHED TO DUCTING, IT WORKS AS A NEGATIVE AIR MACHINE, EXHAUSTING FILTERED AIR OUTSIDE THE AFFECTED AREA. THIS UNIT CAN BE EXHAUSTED TO THE OUTSIDE OF THE BUILDING USING OPTIONAL 20" DUCTING. LIMITED 1-YEAR WARRANTY. THE FIRST STAGE USES (4) PLEATED MERV 9 PRE-FILTERS TO COLLECT AND TRAP POLLEN, HAIR, AND LARGER DUST PARTICLES THE SECOND STAGE USES (4) HEPA MERV 16 FILTERS, WITH A 99.97 EFFICIENCY RATING, AGAINST 0.3-MICRON PARTICLES TO CATCH BACTERIA, ALLERGENS, DUST, MOLD SPORES, AND FUNGI CHANGE PRE-FILTER EVERY 3 MONTHS FOR OPTIMAL PERFORMANCE INDICATOR LIGHT ILLUMINATES WHEN THE HEPA FILTER NEEDS TO BE REPLACED INCLUDES COMPLETE SET OF FILTERS