Code point
U+299C
Glyph appearance depends on your fonts.
U+299C
SmU+299C RIGHT ANGLE VARIANT WITH SQUARE is a Unicode 16.0.0 character in the Math Symbol category. It belongs to the Miscellaneous Mathematical Symbols-B block.
Choose the representation you need, then copy its value.
U+299C
10652
⦜
⦜
⦜
E2 A6 9C
299C
0000299C
%E2%A6%9C
\u299C
\u299C
\u299C
\299C