The Modular Boot System (MBS) is a multifunctional, multi-theater footwear system that will afford the soldier environmental protection and added capability in environmental conditions ranging from minus 20 to 110 degrees Fahrenheit. It is a developmental program designed to replace the Army Combat Boot hot and temperate weather variants, ICWB w/RL and black Cold Weather Boot, which has already been phased out.
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Modular Boot System Wikipedia(Text) CC BY-SA