The size 9 fits true to size for my slightly narrow size 9 feet. I should note Im not using the Bluetooth function (I use an iPod with it), so I dont know how well the Bluetooth works. Una più lucida, l?altra no. This product is a 5/5 for these main reasons: it has excellent grip both inside and outside so you dont slip while walking with them or have your feet slip out in the shower, the holes make it so that it cant drag out excess water onto your floor or shower mats, and they are relatively comfy after use and support the feet well. You could easily buy 5 of these and it would still cost less than a name branPros: An I love these slippers! Because of their softness plus large size, they dont feel comfortable or even safe to walk in. I am very satisfied with the quality of this item. I love the color of these shelves, which will go well with almost any decor. I used it max about 7 times over two weeks, foolishly hoping itnwould get better. It?s smaller than the Nc9.