The Lenovo Business Casual Line is a case collection focusing on lightweight, clean lines and modern details for young professionals daily commute and occasional travel. This Lenovo Business Casual 15. 6-inch Backpack is made of durable and water-resistant polyester with a fairly light weight. The fully padded PC compartment provides great protection to your devices. A reserve charging port for easy charging while on-the-go; Being square in shape and low-key in colour make it suitable for both formal occasions and casual parties.