Fold Drybag UL is about half the weight of its more durable counterpart, Fold Drybag BS. The weight reduction is achieved by the extremely lightweight 15-denier ripstop nylon, which is conveniently translucent, allowing objects inside to be distinguished. The exterior is brightly colored and is silicone coated for water repellency. The interior of the fabric is coated with transparent polyurethane for waterproofness (not submersion). Sizes from XXS through XXL, each size a different color, accommodate a wide assortment of gear, from winter sleeping bags down to pocket knives and headlamps. With the exception of size XXS, each sack is designed with a rounded, rectangular shape for efficient packing. Choose Fold Drybag UL if gram-counting is a priority and organization is critical.