For difficult materials such as oilcloth these braces have become indispensable helpers for me. After I got used to the handling, I now use it even when sewing thicker fabrics in which pins would bend inevitably. The brackets keep the different layers of fabric -or the material you precisely bearbeitet- just as well in the form like pins. There nothing slips and they are shaped such that they can slide easily until just before the presser foot on the sewing machine. There are the staples in the 10s and 50s-Pack. I made the mistake of my first time to order only 20 because I could not imagine how practical are the parts. I can only recommend the same to buy a big pack ...