At Costco & others it’s included with purchase. In my experience never with a new car or tires purchased from dealership. Basically it’s a puncture warranty. They repair or replace tire. Not prorated. I have gotten burned twice with sidewall nail punctures with virtually brand new tires in the Lexus we had. Sidewalk punctures are not repairable. They are only covered with a road hazard warranty. Like most warranties, and insurance it’s more likely that you will pay more than you will collect. It’s worth it for me for the price of mind.