I have a small adult head and these are just a smidgen loose. Called Amazon and was being helped but then was asked to be put on hold and soon after the call disconnected . You have to tighten it quite a bit for it to stay on, and it still shifts around. Ive boycotted all apple products and couldnt be happier. My robe isnt even 2 pounds. Original Nike product. It irritated the top of my feet. Since Google charges $12 for one, I have to say that this is an excellent deal and I recommend. Sound quality loss in high frequency. I have waited and anticipated this watch for a while now.