Tempered Glass is three to five times stronger than non-tempered glass and ten times more resistant to changes in temperature.

The strength of glass is, to a large extent, unpredictable. Since temepered glass cannot be recut after it is tempered, we often have to break it to get it in the dumpster. Sometimes we'll hit it with a hammer four or five times before it breaks. Other times it breaks fairly easily.

But if you hit the glass with something soft, such as a human body, tempered glass will bend an incredible amount and not break. To prove that we performed the following experiment.