The Big Agnes Super Light Girdle Strap is compression for your stuff sack. Turn any stuff sack into a compression sack with this packable strap. Situate the top and bottom appropriately over the top and bottom of your sleeping bag stuffed sack, then cinch. Poof! More room in your pack for that second dinner. Features of the Big Agnes Super Light Girdle Strap Versatile and easier to use than compression stuff sacks Fits stuff sacks up to 18in./46cm