Review on Optimized Massage Flip Flops for Men - Reflexology Comfort Footbed for Improved Health, Pain 👣 Relief, Enhanced Circulation & Energy. Relaxation Acupressure Sandals for Men's Plantar Fasciitis Recovery with Non-Slip Sole by Amanda Hill

I have a size 11.5, and the size 10-11 was too small - and in width, and also the straps were too tight to comfortably fit the leg without squeezing it. I actually prefer flip flops that fit snugly, but that was too much. Size 12-13 was perfect for me, maybe a little big (but still the right choice for me). In other words, it seemed like a size 12-13 was actually a size 12 and a size 10-11 was actually a size 10.5. So if you are between sizes, I would definitely choose the larger size. Otherwise, I really like them after realizing that the size is a bit small.