This morning I was making some reusable sandwich bags out of black nylon and I used a polyester lining. Neither fabric takes a press very well, and it's not easy to pin with regular pins. I found the Wonder clips to be a perfect alternative to pins. I didn't take a picture, but on the other end, I clipped in the long velcro strip. I detest pinning through velcro so the clips were so easy.
I'm glad I bought the larger 50 pack because with making a dozen of these bags at a time, and doing an assembly line sewing, I had 36 of the clips being used at the same time.
Another benefit that I had not realized, is that there is no chance of accidentally sewing over a pin or clip because they won't go under your pressure foot, of course. No bent pins or broken needles today. :) I'll continue working on these sandwich bags tomorrow, adding the other side of the velcro closure and a little decorative patch.
I'll show them to you when I'm done.