The Left One Quarter Block symbol (▎). Copy and paste it, or use its Unicode, HTML, and CSS codes.
More from Block Elements.
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+258E (decimal 9614).
Use ▎ in HTML to render ▎ on a web page.
On Windows you can type it with Alt+9614 (hold Alt and enter the number on the numeric keypad).
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