Waterproof/Reflective Non-slip Rope: The surface of the arm bag has non-slip glue to increase friction, high-quality waterproof material, effectively prevent water ingress, and the surface is designed with highly reflective rope to guarantee the safety of running at night. Silent drawstring/headphone cable hole: silent drawstring, easy to open and close, no abnormal noise when running, easy to use , front arm bag and socket design, sports music at the same time. Double-layer storage / large capacity design: 20 * 9 cm, can store mobile phones, keys, cards banks and other objects, double-layer design, can fix and separate your objects without squeezing each other, easy to open and close, strong and durable. Elastic / Velcro armband: Armband elastic and comfortable, wide adjustment range, wrapping strong, arm-fitting, firm and not easy to shake, unisex, high viscosity Velcro, good firmness, not easy to fall off. Usage: This sports bag can free your hands, you don't have to need to put your phone in your pocket, suitable for gym, workout, sports, fitness, yoga, walking or outdoor activities such as running, cycling, hiking, fishing, paddling solo Canoeing, climbing, camping, tourism, daily leisure. Capacity: using mobile phone with a length of less than 16cm Size: 20*9cm Material: high quality nylon