COLDPRUF Peak Wrmr Prfrm W Mock Blu Sm - Warm Performance WearColdpruf's Peak Base Layer Top Can Be Used As A Base Layer Under A Mid Layer Or Shell During Hard Pushes On Cold Days, Or As A Single Layer During Strenuous Activities On Cool Days. The Super Soft Brushed Microfiber Fabric Contains An Anti Microbial Carbon Agent Which Permanently Staves Off Odors. This Lightweight Fabric Provides A Next To Skin Athletic Fit With Flatlock Seams Which Work Together To Make Your Base Layer One Less Thing To Worry About