A:Answer Yes, the Insignia™ TV Stand for Most Flat-Panel TVs Up to 65" is compatible with VESA 300x300 mounts. This stand supports a range of VESA patterns, including 75x75, 100x100, 200x200, 300x300, 400x400, and more.
So, you should be able to use this stand with your 55-inch TV that requires a VESA 300x300 mount.
If you have any other questions or need further assistance, feel free to ask!