\begin{tikzpicture}
    % BLANK DG
    \node[backtrack] (boxA) at (0, 0) {$$};
    \node[backtrack] (boxB) [right=1cm of boxA] {$$};
    \node[backtrack] (boxC) [right=1cm of boxB] {$$};

    \node[backtrackeq] (boxAeq) [below=-1pt of boxA] {$=$};
    \node[backtrackeq] (boxBeq) [below=-1pt of boxB] {$=$};
    \node[backtrackeq] (boxCeq) [below=-1pt of boxC] {$=$};
    
    \node[backtrack] (boxArev) [below=-1pt of boxAeq] {$$};
    \node[backtrack] (boxBrev) [below=-1pt of boxBeq] {$$};
    \node[backtrack] (boxCrev) [below=-1pt of boxCeq] {$$};
     
    \node (boxAr) at ([yshift=24pt,xshift=5mm]boxA) { };
    \node (boxBl) at ([yshift=24pt,xshift=-5mm]boxB) { };
    \draw [line width=0.4pt,-{Stealth[length=2mm]}] (boxAr)  --node[backtrackstep, above=3.0pt] {$$} (boxBl);

    \node (boxBr) at ([yshift=24pt,xshift=5mm]boxB) { };
    \node (boxCl) at ([yshift=24pt,xshift=-5mm]boxC) { };
    \draw [line width=0.4pt,-{Stealth[length=2mm]}] (boxBr)  --node[backtrackstep, above=3.0pt] {$$} (boxCl);

    \node (boxCrevl) at ([yshift=-24pt,xshift=-5mm]boxCrev) { };
    \node (boxBrevr) at ([yshift=-24pt,xshift=5mm]boxBrev) { };
    \draw [line width=0.4pt,-{Stealth[length=2mm]}] (boxCrevl)  --node[backtrackstep, below=3.0pt] {$$} (boxBrevr);

    \node (boxBrevl) at ([yshift=-24pt,xshift=-5mm]boxBrev) { };
    \node (boxArevr) at ([yshift=-24pt,xshift=5mm]boxArev) { };
    \draw [line width=0.4pt,-{Stealth[length=2mm]}] (boxBrevl)  --node[backtrackstep, below=3.0pt] {$$} (boxArevr);
\end{tikzpicture}