Eureka "OX" & Electrolux "S" Micro-Filtration vacuum cleaner bags.  These generic bags come 9 per package and are guaranteed to fit.   Ideal for For Eureka  920, 6500, 6990 / Electrolux EL6980 EL7000 & EL7020 ie  Oxygen, Harmony series canister vacuums and CV140 central vacuums. For optimum performance, change bags every 1-2 months. Store in a clean, dry place. Part # 135-9