Leaving work and noticed that my tire was flat with an arrowhead shaped piece of metal between the tread. Pulled it out and used the fix-a-flat since I don't have a spare. Pressure held after I aired it up and drove home. Next day removed the tire and took it to Mcfall's, I showed them where I removed the shard and you could see where the goop had come out when I inflated the tire. They said nothing was wrong with the tire and there was no puncture, maybe somebody let out the air! Took the tire to Discount Tire where they found the leak (right where I told them it would be) and patched it.