This is a 010 Editor Binary Template for Stranded II map and save files. 010 Editor Binary Template functionality lets you visualize binary data in a file via a results table with optional coloring. It makes it easier to understand the data.
For more info, see: 010 Editor - Binary Templates - Parsing Binary Files

This makes edits on maps via hex editing easier. For example: Stranded II will leave leftover extensions with the content of a script that's added via the addscript method. Using this, you can easily identify this extension and delete it.