With the built-in contour pocket, you can bring along your smart phone, MP3 player, keys and other important items you need while exercising away from your home. Perfect Fitness Perfect Weight Vest, 40 lb: * Design is inspired by military body armor * Fully adjustable for a customized fit * Provides a slim, comfortable fit * Flat, flexible weights move with your body * Double belly band ensures secure fit * Extra-durable shell with built-in padded shoulders * Road-ready, with high visibility, reflective material for low light conditions * Contour pocket for your smart phone/MP3 player