Kelty Light Year XP 40-Degree Climashield XP Sleeping Bag 40 F/4 C Mummy Insulation: Climashield CP. Shell: NPR241T nylon-polyester diamond cross-dye ripstop. Liner: P300T polyester microfiber pongee Quilt-through construction and chevron stiching. Efficient, form fitting hood. Zipper darft tube with anti-snag design and zipper foot vent