The closure mechanism on this backpack is a zipper. Several materials have been used to make this bag, among them cotton, and it has an 18-litre volume.
From Amazon
Fjällräven Kanken Unisex Outdoor Rucksack available in Deep Red - 40 x 28 x 16 cm
Nordic Outdoor
Fjällräven Kånken No. 2 Laptop 15”