FUNCTIONAL & COMFORTABLE - The Just pack backpack f with built in charging cable offers a convenient way to charge your phone and other electronic devices while walking. The back of the backpack uses a comfortable and breathable mesh design, Comfortable wide breathable mesh shoulder straps with plentiful sponge pad help relieve the stress from your shoulder. One sides of the shoulder strap with lanyard design, can hang sunglasses. Perfect choice as picnic backpack for men women