The Arc'Teryx RHO LT zip-top is an ideal trim-fitting foundation for the maximizing of wicking performance. Lightweight fibers move moisture and a silver fabric treatment reacts with sweat to cut down on back country stench. Arc'Teryx customizes the thickness of each under layer, delivering the exact amount of warmth required for each specific application. Arc'Teryx RHO thermal layers are constructed with less bulk and are detailed for fast moving functionality. The RHO base layers efficiently wick moisture and attack problems of odor accumulation, using textiles that significantly reduce stench on any duration expedition. Like all our products, our insulation layers strike the right chord for the back country bells.