The Ring Operator symbol (∘). Copy and paste it, or use its Unicode, HTML, and CSS codes.
More from Math.
The quickest way is to copy ∘ from this page and paste it anywhere. You can also insert it with its Unicode, HTML, or alt code listed above.
∘ is U+2218 (decimal 8728).
Use ∘ in HTML to render ∘ on a web page.
On Windows you can type it with Alt+8728 (hold Alt and enter the number on the numeric keypad).
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