Mountain Hardwear Unisex Hyper Lamina Reg Sleeping Bag Nylon Engineered to be lightest and warmest synthetic bag available Proprietary welded Lamina construction enhances loft and eliminates cold spots Zoned insulation maximizes warmth where it's needed most Single 5 half length center zip with dual sliders minimizes weight and still allows for ventilation Performance mummy cut is snug, reducing girth, weight, and bulk and maximizing thermal efficiency