The Samaya U/D STUFF SACK is an ultra-lightweight, durable storage bag. Minimalist and easy to use, it provides optimum organization in your pack (spare clothes, food, etc.). Thanks to its Dyneema® Composite Fabric construction and waterproof bottom, it becomes waterproof when hung upside down. Attached to the harness on a gully or icefall, it protects your mittens or belay jacket from spindrifts and moisture. Keep your essentials dry and close at hand!

U/D means "upside down".