MILITARY USGI TENNIER INC. 4-PC MODULAR BIVY & SLEEPING BAGS SYSTEM. Unlock outdoor comfort with the Military Surplus USGI Modular Sleep System. Designed for a wide temperature range and extremely compact, this system includes two versatile sleeping bags, a weather-resistant bivy cover, and a stuff sack, all crafted in the USA by Tennier Industries. Ideal for every camping enthusiast looking to brave the elements. 4-PC Modular Bivy & Sleeping Bags System is. A comprehensive, weather-resistant sleeping solution designed for versatility and adaptability. The system consists of four components. A mild-weather (30 – 50 degrees) sleeping bag suitable for temperatures ranging from warm to moderate cold. Black Intermediate Cold Weather Bag. 10 to 30 degrees. Sleeping bag designed for temperatures between moderate cold and extremely cold conditions. Woodland Camo Bivy Cover. A waterproof, camouflage-covered bivy sack that provides additional insulation and protection from the elements. Combined with patrol & Intermediate bags: -40 for 4hrs. A compact bag for storing and compressing the entire system. Modular design allows for configuration changes to suit various weather conditions and temperature ranges. Gore-Tex waterproof cover provides protection from rain and wind. Enhanced metal snap system connects the bivy and sleeping bags, enabling easy configuration changes. Non-snag side slide fastener and full-length flap along the zipper ensure smooth operation and prevent cold spots. Insulation: 2.4 oz. The system can be configured for various weather conditions, from mild to extremely cold temperatures. Compact storage: The stuff sack allows for easy compression and storage of the entire system. Durability: The Gore-Tex cover and enhanced metal snap system ensure a long-lasting and reliable performance.