Product review (4 stars): SPRING CLAMPS TOO HARD FOR ME - HAD TO BUY WORM-TYPE CLAMPS  -- OTHERWISE VERY HAPPY WITH PRODUCT!
Ordered because it was UL approved.  Happily surprised that it seems tougher than what you would buy at a hardware store (those seem to tear easily).
One note:  I have arthritis in my hands so I could not fully compress the spring clamps.  I had to buy the worm-type clamps to fit this on.