When my windshield was damaged by a rock, I called Safelite because I had seen their commercials on television. The technician came to my office at work and repaired my windshield in less than 20 minutes. He assured me they had a "no spread guarantee." At the time, I believed a ?no spread guarantee? was a guarantee that my windshield would not spread further. What that actually means is that there is a good chance your windshield will continue to spread and they ?credit? what you?ve already paid for your repair towards replacing the entire thing.