Our warmest weight base layer zip neck in the Phase family, ideal for cold days in the alpine, this super-wicking base layer has mid-level insulation to keep you warm and dry, and a zip neck allows fast venting. Hybrid mapping of Phasic(TM) SV (in the body) and Phasic(TM) AR (in the underarm area) fabrics, in addition to the flatlock construction and comfortable next-to-skin fit, eliminates excess bulk and rapidly transfers moisture for efficient evaporation. Engineered for superior moisture management and rapid dry-times during stop-and-go activities, this form-fitting top keeps the user drier and more comfortable. Encapsulated silver-ion fibres provide durable and long-lasting odour control. These snugly-fitting garments are made with stretch fabrics to fit next to the skin to enhance moisture management and thermal efficiency.