Head Cleaning, Pulisci Testine Disk Drive 3,5" Pulitore Floppy, Floppy Clean

Then insert the Cleaning Head disk into the floppy disk drive and let it spin for at least a minute. When your computer finishes spinning the disk, eject it and then reinsert it to continue the cleaning process; the disk should spin inside the computer for at least a minute of active operation.

eBay