You can change this on the software. They are far more comfy than Birkenstock. They fit nice and are very comfortable. They all measures 57/128" to the nearest 128th, and measures from 11. This is a strong point of these headphones, the natural bass spread, which introduces powerful sub-bass without confusing it with middle bass frequencies - this is actually rare in a headphone, sub-bass seems to come from nowhere as an instrument in itself. The only things are that when they are about to die its super loud and it wakes me from my sleep. Tried over 7 case And none of them gave me the fit I needed except for this one. BOTH claim to be Womens Size 9M. I usually find toe post sandals uncomfortable, however having had the Sketchers wedge flip flops for a while I thought Id be safe enough with these. They are very comfortable, easy to connect and sound great.