ESSENTIAL FILTER FOR RUCKACK V-TUF RuckVac Essential Cartridge Filter has HEPA H13 filter media for best filtration efficiency. The V-TUF RuckVac Backpack Vacuum Cleaners must always be used with this caged pleated filter securely fixed inside the vacuum to ensure the dust and air is filtered on passing through the vacuum body, to prevent any pathogens escaping back into the air, therefore also protecting the surrounding workforce. NEVER USE THE V-TUF RUCKVAC VACUUM CLEANER WITHOUT THIS FILTER SECURELY FIXED INSIDE.