Engineered with purpose, the Snugpak Tactical Series 4 Sleeping Bag was built using state of the art materials and ingenious construction methods that provide superior heat retention in extreme winter weather conditions. Snugpak's patented Softie Premier insulation traps heat, while a Paratex Steelplate shell repels moisture. Reflectatherm space-age heat reflective fabric and TS1 (Thermal Suede) make up a lining that is luxurious and retains body heat, giving you the protection from the elements you need to get a good night's sleep.