⚠ Before adding to cart, make sure it is sold by PORTHOLIC instead of others. This is for not getting faulty products and you will never heard them back for refund. This armband could easily fit a big phone like iPhone 7plus with large protective case, such as Otterbox, Commuter Series and Lifeproof case. If you are looking for a smaller model, kindly contact us for recommendation. The capacity of this armband is equivalent to an iPhone 8plus in an otter box. 6.8'' Diagonal Screen Size. 【Fits Small & Larger Arms】Two fastening sizes and a 6" Extension Strap easily fits arm size from 9 to 18.5 inches. There's reflective strip to keep you visible and safe in the dark. Key and card holders are built-in on the backside for you to store key, ID and credit cards. 【Updated Version】COMPATIBLE WITH FINGERPRINT UNLOCK FUNCTION and iPhone 7 plus home button access. Made of soft and breathable Lycra and Neoprene, this fitness armband is skin-friendly, light weight, and odorless.