Overview of the Lenovo 15.6" Laptop Everyday Backpack B515 in Blue Built for the daily grind, the Lenovo 15.6" Laptop Everyday Backpack B515 is composed of premium materials that are resistant to tearing and water. Its main compartment is roomy enough to accommodate personal belongings for a business trip, the gym, or other events, and it fits up to 15.6" laptops.