The Z Notation Bag Membership 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+22FF (decimal 8959).
Use ⋿ in HTML to render ⋿ on a web page.
On Windows you can type it with Alt+8959 (hold Alt and enter the number on the numeric keypad).
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