Eagle Creek Pack It Compression Sac Set (Small/Medium/Large), No Color, 3pc Set Nylon yarns reinforce against tears Reduces volume up to 80% Patented one-way pressure valve Patented zip closure at top "Second trip to asia for three weeks each. Flying, trains, buses to move around countries. With these bags, I could travel with compact sizes, yet take all I needed. Easy to load and unload for the many stops I made. Simple, durable and very usefull." - Rich