We have to understand that during repairs there's always a slight possibility, 0.1% to 1%, that a crack that is repaired by us can spread. We therefore cannot provide a lifetime warranty on cracks however all our chip repairs come with lifetime warranty. We require you to keep receipt of the service done for your own records no warranty service will be provided without receipt. If any chip repaired by us spreads into a crack we will repair that crack for free at no additional/hidden charges. If we cannot stop the crack we shall refund you the amount on the receipt. In the unlikely event you need to take claim the warranty, simply come to one of out tents as per your convenience. Alternatively you can also forward your receipt via email: stealth@stealthwindshieldrepairs.com, or call us at the number: 18884442579