You can never guess what this is! ( I'll be stunned if you can )

One of my colleagues showed me this, and I am surprised that such thigs also exists and there's a market for it and god damn people are buying. Its actually useful though. Can you guess what this is and its use case?

https://preview.redd.it/zvoze480t7ng1.jpg?width=1280&format=pjpg&auto=webp&s=fcf4fc8cbe5f0141de0ccc87f8e8bdfb439d7495