Foam edge corner protection what to use ?

I saw a post where someone had use some type of plastic (I think) bendable edge protector, for the exterior corners of their foamie. I think it was for drywall work, . It was white, with lots of small holes. If anyone knows what I'm talking about please let me know where to but some. It was applied to the foam/then covered with canvas.
Or if anyone else has use some other form of edge protector. Please give me some ideas of what to use.
Or if anyone else has use some other form of edge protector. Please give me some ideas of what to use.
