Code point
U+2997
Glyph appearance depends on your fonts.
U+2997
PsU+2997 LEFT BLACK TORTOISE SHELL BRACKET is a Unicode 16.0.0 character in the Open Punctuation category. It belongs to the Miscellaneous Mathematical Symbols-B block.
Choose the representation you need, then copy its value.
U+2997
10647
⦗
⦗
E2 A6 97
2997
00002997
%E2%A6%97
\u2997
\u2997
\u2997
\2997