Am I allowed to sell boxes that allow customers to stream movies, tv shows and games for free?

You may be liable for copyright infringement if you knowingly engage in commercial dealings with devices (such as set-top boxes (also known as “white boxes” or “grey boxes”)) or software applications or services, that have a limited or no commercially significant purpose or use besides facilitating access to copyright infringing works.

Commercial dealings in such devices include selling, offering or exposing for sale by way of trade, distributing for the purpose of trade, exhibiting in public by way of trade, or offering such services in exchange for payment.