Code point
U+301A
Glyph appearance depends on your fonts.
U+301A
PsU+301A LEFT WHITE SQUARE BRACKET is a Unicode 16.0.0 character in the Open Punctuation category. It belongs to the CJK Symbols and Punctuation block.
Choose the representation you need, then copy its value.
U+301A
12314
〚
〚
E3 80 9A
301A
0000301A
%E3%80%9A
\u301A
\u301A
\u301A
\301A