For compatible computers such as Amstrad / ZX Spectrum +3. 3" Disk Turning Knob Small (colour may vary). 3" Disk Turning Knob Large (colour may vary). Slide the disc in as per the arrows which holds the protector open and place it on a flat firm surface like a table with the disc slightly over the edge so that you can then turn the wheel and clean both sides with a cotton bud / cloth.
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