This product is made of high quality polyester,which is waterproof and breathable, with slim protective cases, adjustable arm band large range with two fastening sizes supports any arm girth from 8- to 16- to protect and stabilize the device without slipping or constricting during your indoor or outdoor activities. It is great for gym, high intensity workouts, extreme exercise, fitness, yoga, walking or outdoor activities. Measuring 7.3*3.9*1.6 inches, this custom black waterproof sports armband phone holder. Usage Scenarios: Office supplies, school stationery, corporate promotions, trade show giveaways. Customization: Logo printing available with multiple packaging and color options. Product Highlights: Portable, durable, practical for daily use.