To prevent this, most Shark vacuums have a switch to shut off the brush roll. This essentially puts the vacuum in hard-floor mode and delivers gentle yet effective cleaning. DuoClean is a ...
Hardfloors (wood & linoleum ... but it struggled with the flour that was right at the edge, so Shark's claim of full-width brush-roll cleaning might not be completely accurate.
Shark vacuums that feature DuoClean have two brushrolls within the floorhead. On older models, it's just called 'DuoClean', and the floorhead has a soft brushroll to clean and polish hard ...