DESC: The Big Agnes Crystal 30-Degree Sleeping Bag uses Dualmax construction to combine 650-fill down and PrimaLoft insulation, making it lightweight and warm when wet. The unique combination of insulating materials in the Crystal Sleeping Bag is ideal for wet-weather camping in the spring and fall. Like all Big Agnes sleeping bags, the Crystal has insulation only on the top side and uses an integrated sleeping-pad sleeve on the bottom to hold your insulating pad in place. By taking out the insulation under you, which becomes compressed and useless, Big Agnes cut the weight of the Crystal sleeping bag to only 2lb 10oz (medium size). *Compatible with 20in-wide rectangular pads.