This mounting base allows tool-free installation of accessories on aluminium fishing boats in the USA with 45 degree gunnel tracks, including Lund, Lowe, Excel, Express and early model Crestliner boats. Simply take it out and flip it over to change it from a vertical mount to a horizontal mount base. Installed with the mounting port horizontal is best for fitting navigation lights, camera mounts, rod holders and cutting stations. Flip it over so the base is vertical, and then you can fit rod holders, drink holders, fillet tables, depth sounders and much more.