iPad Minimal Sketch
From the author: “I needed a minimal ipad for my current project. And I thought to myself : “it will be even better if I’ll share it to all sketch users”. Here it is ;)”.
So it’s probably free to use for all purposes. Ask to be sure.
Helpful hint: Dribbble users are nice. If the license is unknown, it is usually because they forgot to mention it explicitly; not because they were being stingy. Ask nicely and they will probably allow you to use it.