Tool palettes are used to organize tools that range from blocks to commands to hatch patterns, and are displayed as part of the Tool Palettes window (TOOLPALETTES command).
You customize tool palettes by dragging and dropping files from File Explorer, objects from the drawing area, contextual menus of the Tool Palettes window, Customize User Interface (CUI) Editor, or Customize dialog box. Each tool palette that is created represents a tab on the Tool Palettes window.
The default folder used to store tool palettes is:
%AppData%\Autodesk\<product name>\<release>\<language>\Support\ToolPalette\Palettes