The top strap on this sandal has NO flexibility to make it looser or a little tighter without a lot of trying to soften it up and Im not sure that you really can. All in all it is still the better of the 3 Ive had. I bought them on a whim because I needed them for our camping trip and was pleased to find they were so easy to put on my 2015 Subaru Crosstrek. When I do a downward dog, the opening slips down and covers my mouth and nose sometimes. I just received this speaker like 15/20 minutes ago, literally was excited to get it and it got here pretty quick. Thats roughly 20 hours of use. It works great for this purpose! Finally spent the $$ on a premium phone but didnt get a premium experience with this phone. Im in no way a stereophile. I was unable to get sound in both sides without contorting the wire and holding it in a specific position.