The 6 Pcs Black Drawstring Backpacks are lightweight, large in size, and made of durable polyester material. With adjustable backstraps and a drawstring closure, these cinch sack packs are perfect for gym, sport, and travel activities. Each backpack has a storage volume of 1200 cubic centimeters, making them ideal for middle school students and big kids on the go. The solid black color and versatile design make these drawstring bags a practical choice for various outdoor adventures.