【Elastic Two-Layer Structure】This running armband features an elastic two-layer structure that securely holds your smartphone while running or jogging, is gentle on the skin, and provides comfortable, long-lasting use. 【Compatible with Various Sizes】 The elastic band fits smartphones from 4.7 to 7.2 inches. It allows full access to screen operation, camera, fingerprint authentication (Touch ID), and facial recognition (Face ID). Even if side buttons or the camera are covered depending on the smartphone model, adjustments can be made. 【Breathable Design】 The internal breathable structure prevents sweat buildup during running and marathons, maintaining a comfortable fit. The textured silicone pads dissipate heat and reduce stickiness from sweat. 【Washable & Replaceable Belt】 The elastic belt is washable, allowing you to keep it clean by removing sweat and dirt. The band and pad can be separated, and the armband can be purchased separately for replacement. 【Universal Phone Holder & Adjustable Armband】 The flexible silicone material and highly elastic holder accommodate smartphones from 4.2 to 7.2 inches (latest verification supports 4.7 to 7.2 inches). The armband uses Velcro for adjustable positioning and tightness, with belt sizes / L size: 25cm to 40cm. The popular Taiwanese brand BONE, which is also popular in Japan, has gained high praise from many users through years of sales, development, and improvement. The "BONE Run Tie" is recommended as a standard running smartphone holder.