EnviroCare Replacement Micro Filtration Vacuum Bags for Hoover Type SR Canisters 12 pack Hoover WindTunnel 2 Type W2 Vacuum Bags - 12-pack Microfiltration with Dust Seal Closure - 6 Pack, Compare With Hoover Part # 401010W2 Which Only Has 2 Bags. 99.9% Allergen Filtration - Traps Microscopic Particles and Allergens. Fits Hoover Windtunnel 2 Models: U8311-900 & U8315-960 Upright Series OEM 401010W2 - By Envirocare Part #329