Our lightest racing shoe, the Nike Streakfly is all about the speed you need to take on the competition in a mile, 5k or 10k race. Low profile with sleek details, it feels like it disappears on your foot to help you better connect with the road on the way to your personal best. DJ6566-100 Under 75 miles ran in this pair. The shoe still feels great. You can see in the last picture that the upper appears to be pulling away from the midsole. This is more cosmetic than anything. There is no functional issue with these shoes.