This thing does exactly what it says on the tin - it's a sturdy metal plate for a Gravity stand extension. It has plenty of features - nice big rubber feet, handles for... well, handling, but also cable management, and 2 screws that can be used for even more extensions like a mic stand or gooseneck. Great stuff!
The only usability complaint I have is that it fits the Gravity extension so well, that it completely covers it, making my big midi keyboard below hard to see while playing standing up. Not really a fault of the product, as it's meant to turn your keyboard stand into a table, but something to be aware of when purchasing.
Great construction, great fit, great looks. It's worth it.