Sea to summit compression sack blue large description when you need a durable compression sack this is your go to a classic design that will help compact the contents of your pack features flip top lid design prevents strap tangling made of 70d pu coated nylon 4 straps for even compression eliminates bulging extra long straps so its easy to fill these to max capacity nylon webbing pull handle on bottom note seams are not tape sealed therefore this product is not waterproo