Seeing all the reviews that said fit as expected caused me to get my normal size, 8. Content Note: a couple intimate situations, not terribly detailed, easily skipped. Fits nicely in my gym bag, too (my gym bag is actually a nice diaper bag I bought on Amazon with lots of pockets and insulated “bottle” holders inside to keep my drinks cold). It can hold well over 200 pounds. Year after year! If I need more I will definitely will buy. I don’t know what it’s like to use this on a mountain bike trail with a lot of bumps but I would say this would be a suitable phone mount for a mountain bike trail! 😁UPDATE: Bought another one. 0 fits okay I guess like a 9. This case fits super snug on my new AirPods pro and the carbon fiber is very nicely woven, no defects and it’s all nicely polished.