The closure mechanism on this hiking backpack is a zipper. The material of choice for this bag is nylon and it has a volume of 25 litres.
From Amazon
Salewa Alp Trainer 25 Backpack - Black, 55 x 24 x 27 cm
SH24 Outdoor Shop
Salewa Alp Trainer 25L Rucksack
Trekkinn
Salewa Alp Trainer 25l Backpack Black
OnBuy
Salewa Alp Trainer 25 Backpack - Black, 55 x 24 x 27 cm