Fred Kelly Picks Delrin Slick Regular Heavy Set

I had to buy a set of thumbpicks to replace an old piece that didn't fit well. It is a bit tight for me, the circumference of my thumb being about 6,5 to 7 cm. My recommendation is to try the large set if you have comparable thumbs to mine.
Back to the product. What else is there to say? The pick does what it's supposed to, even though it's a tight fit, I could still play for a while. It does not twist or slip off and the material seems durable enough.