10 consecutive impacts on insoles

Here are 10 pairs of ACI children's Flyers insoles, randomly selected from our warehouse. I have a 3kg lead ball in my hand and this is a piece of 3mm ordinary glass, we will use this piece of glass for the experiment, the first group, the second group, the third group .... The tenth group, you can look at this piece of glass is now intact, these traces above are offset printing. well, you may say that this piece of glass is specially made, but now, let`s see