I got a flat tire today. I figured it was because I hadn't checked my pressure lately and so I got a pinch flat. However when I got back to the car I found a piece of plastic shaped like a spike in the side of my tire. Looking at the tube it turned out the puncture was right where the spike was in the tire. I guess I was lucky it didn't puncture the replacement tube somewhere on the way back. This is a picture of the Henry's fork area. King's Peak is the distant peak about 1/3 of the way in from the left edge of the picture.