Layer on the warmth with our ECWCS Gen III Level 2 Thermal Grid Fleece Underwear! This thermal undershirt is classified as part of the cold weather system created and primarily utilized by the US Army. Level 2 garments, such as this, provide light insulation, providing an extra layer of defense against frigid conditions. The grid fleece pattern on the inside is designed for maximum breathability and improved moisture-wicking properties, as well as smart odor control. This shirt zips up to make a turtle neck also features thumbholes in sleeves for adding multiple layers. Stay Warm with Less Bulk Stay warm and toasty with our thermal ECWCS underwear. Wear easily under your clothes for an extra layer of super warmth - and no bulk showing! Layer on the warmth with our ECWCS Gen III Level 2 Thermal Grid Fleece Underwear! Throw on these super comfy fleece-lined thermals for an extra layer of protection against the cold. They are moisture-wicking, anti-odor, and remain breathable, keeping you warm and dry. As part of the Extreme Cold Weather Clothing System (ECWCS), this midweight Gen-III Level 2 thermal underwear acts as an extra barrier between you and the cold air. Offering light insulation, it easily fits under your clothing while limiting the bulk factor. It also features flat-locked construction and a fly front.