For the Modular Sleep System we sell all of the pieces individually as well as a set.  

The Military Modular Sleeping Bag consists of two Mummy-style sleeping bags - the Patrol and the Intermediate Cold Weather. Each are constructed of water - resistant, ripstop nylon. Each Military Sleeping Bag is fully functional independently. For a temperature to -30degrees, insert the Intermediate Cold Weather bag inside the Patrol bag. Each bag is compatible with the vapor permeable bivy cover. When all 3 compartments of the Gortex 3-part sleeping bag are used together, the system is rated to provide 4 hours sleep at -40 degrees. A compression stuff sack is included and detailed below. Non-flammable and machine washable.

1. PATROL BAG FEATURES: Temperature to +30degrees, reversible double-pull(opens end to end) slider allows top or bottom ventilation, non-locking slide fastener self repairs if jammed or snagged, draft flap prevents heat loss, hood adjusts for heat retention, includes nylon drawcord and barrel lock. Color Green. Order your Military Modular Sleeping Bag today.
2.  INTERMEDIATE COLD WEATHER BAG FEATURES: Temperature to -10degrees, from from cold spots, insulation does not migrate in the bag, anatomically designed foot box contains twice the insulation as the bag, sewn-in, quilted chest collar prevents air drafts up and down through the hood, hood adjusts for heat retention; includes nylon drawcord and barrel lock.
3. Bivy Cover STUFF SACK FEATURES: Compressible to one cubic foot, six 1" wide nylon webbing straps by ladderlock buckles, reinforcement webbing is sewn around the circumference of the bag, nylon drawcord closure with a barrel lock. 
4. Sleeping Bag stuff sack

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