Steel, elevated walkway for controling drydock operations, assembledfrom the following, 2 ea catwalk beams /long/ mark no. Ds-4, 4 ea beambrackets mark no. Ds-16, 4 ea panels mark no. Ds-3, 24 ea hook bolts markno. Ds 18, used for p-series pontoons, navfac dwg 816468, mark no. Ds-7