Code point
U+220E
Glyph appearance depends on your fonts.
U+220E
SmU+220E END OF PROOF is a Unicode 16.0.0 character in the Math Symbol category. It belongs to the Mathematical Operators block.
Choose the representation you need, then copy its value.
U+220E
8718
∎
∎
E2 88 8E
220E
0000220E
%E2%88%8E
\u220E
\u220E
\u220E
\220E