Hi, Ruth!
I have one made of plastic pipe that I bought at JoAnns Fabric. Don't know the brand. It comes in 2 sizes, square or rectangle. There is a plastic sleeve that snaps over the pipe. I love it. It never pops off and is easy to adjust once it is broke in, a little tight 'til then. Being rectangular, I don't have to move it as much as the round ones. This one is worth looking for. I use it for hand quilting. I haven't done machine quilting much, but didn't use a frame when I did mine.