I used for the first time after getting a piece of flint stuck in my tyre. The cut was too large to trust stans to seal it. It was a tight fit to push into the hole so although the hole was much bigger than a thorn the smaller worm was the right size. It sealed the hole. I had to add air to re-inflate the tyre to normal pressure. three weeks later (and 200 miles off-road South Downs area) and the plug is still working perfectly. Bit pricey but it saved others time waiting for me to fix.