The birth of Monthbell's waterproof trekking pack. The combination of the waterproof inner bag and roll up closure effectively prevents water penetration. Without a top lid, the roll up closure also allows for quick access to your pack's contents. Ushering in a new generation of backpacks.This model provides excellent stability while maintaining a slim silhouette. Won't hinder your movement for smooth trekking even through narrow mountain trails. Includes a convenient pocket for storing small items at the front.