You close this bag with a zipper. This particular bag is made from polyester.
From Amazon
Trust Atlanta Sustainable Laptop Bag 15.6 Inch with Shoulder Strap, Recycled Plastic Laptop Case, Eco Bag, RPET Work Bag, Durable Carrying Case for Travel, Business, Office, School - Black
Technoworld PLC
Trust Atlanta notebook case 40.6 cm (16") Briefcase Black
This product is also available at 6 unverified merchants.