Phase Series: Moisture wicking base layer for interval activites. AR: All Around. Provides high performance weather protection and highlights a range of features to give All Around versatility in multiple activities. The men's Phase AR Zip Neck Top from Arc'teryx is a lightly insulated base layer engineered for optimal moisture management during stop and go activities. During active phases the men's Phase Zip Neck Top moves moisture and wicks across the entire garment with the help of PhasicTM AR and SL fabrics, aiding in temperature regulation. Entering the rest phase the Arc'teryx Phase AR Zip Top broadly disperses moisture so it evaporates quickly, speeding fabric dry time in order to keep the user warm and comfortable. Encapsulated silver ions provide durable and long lasting odor control. Features: Moisture wicking Breathable Lightweight Quick drying Minimal odour retention Odour control fabric treatment Hydrophobic materials will not absorb water Mechanical stretch textile for unrestricted mobility Flatlock construction improves next to skin comfort Anatomical shaping for fit and comfort Gusseted underarms Laminated chin guard Quick pull 12 length zip for easy venting Long sleeves Non chafing label Next to skin fit Weight: 165 g 5.8 oz Activity: All Round Materials: PhasicTM AR 87% polyester, 13% polypropylene, UPF 50, 145 gm . Double knit textile with mechanical stretch composed of multi dimensional polyester yarns that wick moisture laterally to dry quickly, plus polypropylene yarns that have silver ion encapsulated into the fibre for long lasting odour control. The smooth outer face is durably pill resistant and a lightly lofted interior adds light insulation. PhasicTM SL 70% polyester, 30% polypropylene, UPF 25, 98 gm . Reduced yarn size of polypropylene lends soft touch to 100% hydrophobic jersey knit textile with mechanical stretch. Composed of multidimensional polyester yarns that wick moisture laterally to dry quickly, plus polypropylene yarns that have silver ion encapsulated into the fibre for long lasting odour control. Very light weight with a smooth outer face that slides easily under other layers.