At the peak of your workout, Mother Nature may try to stop you. Don't let her! When the heat sets in, stay cool with our Woolverino Micro Sleeveless. The range of movement you expect from a sleeveless combined with the extreme moisture-wicking power of Merino Wool will keep you going even when the elements try to stand in your way.  Fabric Fiber Content: 84% Merino Wool, 12% Nylon, 4% Spandex OEKO-TEX® STANDARD 100 Certified Woolmark® Certified Responsible Wool Standard® (RWS) Certified Knit: 145 g/m2 Micro Weight Jersey Knit Microns: 17.5 Micron Fibers UPF Rating: 20 Total Easy Care: Machine Wash and Dry Wool Source: Australia Imported. Features Neckline: Crew Neck Yoked Shoulders: Seams are offset from your shoulder for a more comfortable backpack fit Tagless Construction: No itchy neck tags Flat Lock Seams: Prevents Chafing Layer Type: Base Layer Fit Type: Regular - Standard fit with a little bit of room to breathe, but not too baggy Model Features: The model in ash grey is 5'10 / 150 lbs wearing a medium Runs True to Size - If you like a tighter, more athletic fit, try sizing down Weight: Size Large = 4.8 oz. (136 grams) Style #: 1003 Uses Ideal Seasons: Spring, Summer, Fall Activities: Everyday Wear, Hiking, Camping, Biking, Running, Fishing, Hunting, Snowsports Temperature Recommendations: 30°F and up while active, 60°F and up while inactive - Learn More Care Washing and Drying Instructions - Learn More Turn Inside Out Machine Wash Cold: Gentle cycle with like colors Detergent: Mild or wool-specific Tumble Dry: Low heat Storage: Place in an airtight container when not in use for long periods of time Do NOT Use: Fabric softener or bleach! Product Story Woolverino Woolverino's Core Spun Technology brings you a merino garment that is durable, athletically fitted and high-performing. Warm when you need it. Cool when you don't. Nylon inner core offers strength, elasticity, resiliency, and durability. Merino Wool outer sheath provides insulation, moisture-wicking, and UV protection.