DON'T USE IT ON ACRYLIC! Ask me how I know...removing it from my acrylic ruler also took off most of the markings. I used it solely to smooth a quilt I was spray basting and it was a wreck. I also couldn't get it off my acrylic nails...I now wear rubber gloves when I'm basting.
That said, I LOVE it for spray basting quilts, and would never go back to pin basting.