HEPA activated carbon air filter cylinder 145mm x 250mm is designed and applied for HVAC air handling system, which is together used with Pre filter panel or V type filter. by vibro machine, more activated carbon pellet is packed and no air leakage in carbon bed depth. before packing carbon pellet, anti static treatment is proceeding. according to clients requirements, white zinc or yellow zinc galvanized filter mesh could be used and opening rate could be from 55% - 70% for option.