The back shoulder of this bag is designed with an automatic absorption shoulder strap buckle, which allows you to easily take off the bag or carry the bag, which is convenient and fast.The Crossbody backpack sling bag Size: Upgrade model size:4.3 x 11 x 16 inches /11 x 28 x 41 cm. This Black sling bag has enough room for all your essentials such as books, mini Ipad, phone, umbrella, sport equipment etc. in addition, a inter layer insert pocket inside the main pocket holds the power bank for the charging port-perfect for daily used,the side pocket can hold your bottle.Adjustable Reversible Shoulder Strap: The Black Crossbody Sling bags for men with D-rings on the lower part, the adjustable shoulder strap can be connected with the left or right D-ring for your preference, so that it is convenient to wear on your left or right shoulder.The Adjustable shoulder strap can be adjusted to the length you like.USB Charge Port: This Small Backpack does not contain a charging power supply. This hiking sling backpack for women men comes with a USB charging port great convenience for charging your electronic devices via connecting your own power bank, you can connect your phone to and easily charge during outdoors and travel. anti-theft zipper, safe pocket, premium buckle.Lightweight & Water Resistant:This Upgrade model black anti theft sling bag for men women is made of high quality nylon water resistant material. They are soft, washable, Water Resistant, wrinkle-free, and wear-resistant. Water resistant exterior keeps your clothes and items dry; Excellent workmanship which shows your outstanding temperament.(Tipsplease do not expose to heavy rain or water all the time.)Multi-occasion: This sling pack bag/ daybag /Chest Bags for women & men is perfect for any occasion. Sling backpack bag for hikingwalking bikingcyclinghuntingtravelbusinessgymcampingbeach and everyday using. perfectly works as sling shoulder pack bag, wear this black sling bag over either shoulder comfortably, or across the chest to deter thieves and keep your hands free.