I use mine exactly as Hdm described, to remove loose stuff dredged up by my Hunt CF brush before wet cleaning. My Nagaoka also leaves a film, though it cleans off easily and seems to decrease as the roller ages.
Highly recommended convenience tool for removing loose dust and cat hairs, provided you wet clean and vac afterwards.
Highly recommended convenience tool for removing loose dust and cat hairs, provided you wet clean and vac afterwards.