I have two so I can charge one while using the other. So these lose a star for price. Usually a size 8. Id probably be less inclined to use it with my CX900 since I have other, better (cabled) options with that camera. I have a slightly narrower than a "B" (medium width) and these fit well without gaping around the upper. I just plugged it in and it worked. Thank you for your attitude, I wont bother you again ever. Edit: The weight is actually distributed with the top strap which anchors to the top part of the back, so this part does serve a purpose. Love that I can now track cadence, speed, and watts. I wear a size 9 and ordered a large and they fit perfect.