Hoover WindTunnel Air Model UH70400 & UH72400 Primary Filter. Designed by FilterBuy to replace Hoover Part # 303903001. Washable and Reusable. 1 Premium Allergen Primary Vacuum Filter Premium Allergen Filters Designed by FilterBuy to fit Hoover WindTunnel Air Models UH70400 & UH72400. Replaces Hoover Part # 303903001. Vacuum FilterBuy: Breathe Better!