I have one of these in the box but I have never used it. I got it more of a curiosity. However, I remember my grandmother darning socks by hand when I was little. She had this little bulb-like thing she stuck inside. Having raised two kids as a single mom (widow) during the depression, she was always thrifty. Now that I think about it, I wonder why she didn't use one of these. She had a Singer 66 and certaintly could have.