Yeso Water-resistant Outdoor Hiking Backpack - Large Capacity Women And Men's Travel Sport backpackPolyester Material Unique and fashionable appearance design Large capacity, multi-function and super storage capacity New 3D high-tech ventilated shock proof and pressure reduction system. High elastic dense honeycomb mesh foam cushion with the thickness up to 18mm, Y-shaped groove with all directional ventilation Optimal nylon washer fabric from Taiwan, without shrinkage and color fade, Water-resistant Large:High 18.5 inch,wide12.2 inch,thick5.9 inch.Small:High 16.9 inch,wide 11.8 inch ,thick 4.7 inch.