\documentclass{article}
\usepackage{pstricks}

\parindent=0pt
\pagestyle{empty}
\begin{document}

\begin{pspicture}(7.5,0.5)
%  \psset{linewidth=15pt}
  \psline[%
    doubleline=true, doublesep=10pt,doublecolor=red,%
    linecolor=blue,linewidth=4pt](0,0.25)(7.5,0.25)%
\end{pspicture}

\end{document}
