Ive had this same style Isotoner many times (they dont last forever). They do not fit securely for intense sports activity, however, I did jostle my head around to see if they would drop off my head and did they remained in place. Impressive. I think if you had regular width or narrow width feet, these would be very comfortable. I also purchased separately the customized mod kit covers for $20. Battery life is great as well, very happy with this purchase. The last straw was just now I accidentally stepped on a piece of packing tape and it touched the toe of my shoe. The two pieces don?t have a way of sticking together, one lays on the other, but this makes it easy to slide wider or more narrow. They would fit nicely if there were a few more inches and more velcro space. I love this particular sandal, because it has three straps and sits to the form of your foot.