Double Commander is an open source Mac file manager that was inspired by the Total Commander utility. Its dual-pane view, ability to preview files directly from the main window or options to define various global hotkeys are only a few of the multitude of offered features.
The application comes as an alternative to working with Finder, Mac's default file manager, for handling the documents within your computer. You can define a wide range of global hotkeys for easily manipulating files within folders, copying the path of a document, comparing directories, and so much more.
Another important aspect of using this program is that it comes with multi-tab support. This feature might prove to be of good use when you need to handle multiple folders in the same window.
Furthermore, the app comes with an integrated image viewer, helps split and compress files with just a few clicks, lets you choose from a wide range of display modes (Thumbnails, Brief View, etc.), etc.
To be honest, I can't find a single bad thing to say about this program. It provides you with many useful features, has a very intuitive interface, and is free. So, you should definitely give it a try if you're looking for an advanced file manager for your Mac.