Genuine Riccar brand replacemernt bags specifically designed to fit Radiance Premium and Radiance models only.  HEPA Filtration, multi-layered, disposable cloth bags.  Takes on more dirt than a standard paper bag which in turn allows for longer usage.  HEPA filtration assists in easing allergy and asthma sufferers' systoms by collecting finer particulates including dust mites and pet/carpet allergens.