A letter inside a circle naming the solvent a cleaner may use.
A letter inside the dry-cleaning circle tells a professional cleaner which solvent class is permitted — P for perchloroethylene and hydrocarbons, F for hydrocarbons only. It is addressed to the cleaner, not to the wearer.
In the ISO 3758 system a letter within the circle identifies the class of solvent permitted for professional dry cleaning.
Contexts: Laundry
Written for the professional cleaner rather than the garment's owner, which is why the letters are not explained anywhere on the label.
Contexts: Laundry
A plain circle outline containing a single capital letter, sometimes underlined by a short horizontal stroke beneath the circle.
Both are letters in a circle. P and F are dry-cleaning solvents; W is professional wet cleaning, which uses water.
Both are built from circles, and both are used in laundry contexts.