The dimensions are correct and the cuff fits well s4; the marks corresponding to the volume and on / off buttons are well placed. The phone looks rather well protected. So much for the positive. On the negative side, condensation tends to accumulate in the cuff when it is worn on the arm. After an hour, there is concern for the health of the phone. Furthermore, I do not find it very comfortable cuff and had appreciated to place most freely - the investment is limited by the dimensions of the strap. In short, a basic cuff I would not recommend.
