Unusual flag?

[Olle]

I bought some books at an estate sale, and found this in the pile. The strange thing is that it's printed on canvas, and one side only. There's also an SS stamp plus a pinwheel with a swastika on the back. I haven't measured it yet, but the picture shows it on the hood of my car to give you an idea of the size.

So does anybody know what it is, and if there's any value to it?