I will have to agree with Mr_P as it is not uncommon for someone in a passenger car to be running 60-70 mph and some idiot coming from the other direction be running 60-70 mph and veer into there lane and hit them head on and that would be equal to 120-140 mph head on crash into a concrete wall......"And It Happens All The Time"!And more passenger cars are left out in the sun than race cars and yet the 2" factory belts are good for life,no need to ever replace!