When I first got my machine, I looked at it and went "what is this for". Stuck it in the case for the machine and never looked at it again. After a few years of owning my machine, someone explained what it was and talked me into trying it out. I have been hooked ever since. Love it when I am piecing blocks, especially when chain piecing. I have found it also very helpful when doing top stitching on applique pieces.