Experience fresher, cleaner air with our replacement filters, made specifically for Lasko Tower Fan models OST100 and RST200. Say goodbye to hair, dust, volatile organic compounds (VOCs), and unwanted odors as our CarbonX filtration system kicks into gear. To keep your fan performing at its best, don't forget to maintain it regularly. Clean or replace the filters every 90-120 days under normal use. Stick with a brand you trust for replacement filters. Lasko, Better Air Starts Here.