This electrostatic Super Air Clean Filter comes as the standard exhaust filter in Miele S142 to S157 Universal & Little Giant Uprights. It is designed for those desiring outstanding filtration but who do not have dust related sensitivities which require the level of filtration that meets the stringent HEPA specification. When purchasing a box of Miele paper bags, you will also received one of these filters plus the electrostatic secondary filter packaged with them. Purchase this pack of three Super Air Clean Filters if you wish to change them more frequently than every five bags.