The Left Three Eighths 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+258D (decimal 9613).
Use ▍ in HTML to render ▍ on a web page.
On Windows you can type it with Alt+9613 (hold Alt and enter the number on the numeric keypad).
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