The air purifier’s modern style molded plastic casing is light weight, durable, attractive and importantly, have air tight seals for maximum air purification. Molded plastic casing is the most preferred option of leading manufactures. Independent Australian tests confirm nil air leakage for both Winix models.
Air purifiers with pressed steel casing have lower production costs, but can be quite heavy (up to 20+ kg). If accidently dented there may be increased risk of air leakage around the filters.