\begin{tikzpicture}[x=32bp,y=24bp]% 4x3 \clip (0,0) rectangle (10,10); \path [fill=black!25] (0,0) rectangle (10,10); \draw [thick,black!40] (0,0) -- (10,10) (10,0) -- (0,10) (5,0) -- (5,10) (0,5) -- (10,5) ; \path [draw,ultra thick] (0,0) rectangle (10,10); \path let \p1=(5,0), \p2=(6,0), \p3=(.4,0), \p4 = (.48,0) in node at (5,5) {\sffamily\fontsize{\x1}{\x2}\selectfont A} ; \end{tikzpicture}%