Smartwool Merino 150 Baselayer Short Sleeve - Men's Light Gray Heather Extra Large. The year-round Merino 150 Base Layer Short Sleeve is up to the challenge. With our Core Spun technology we've wrapped Merino around a nylon core for added durability while still keeping the comfort of ultra-soft responsibly sourced Merino next to skin. And select colorways feature a more responsible plant-based-dye technique. Built for consistent comfort even when wearing a pack this shirt is ready to explore the world on your back. Specifications for Smartwool Merino 150 Baselayer Short Sleeve - Men's: Manufacturer: Smartwool Sleeve Length: Short Sleeve Age Group: Adults Apparel Fit: Slim Gender: Male Application: Layering Casual Shirt Style: Lightweight Thermal Fabric/Material: 87percent Merino Wool 13percent Nylon Core Weight: 4.7 oz Lining Material: 87percent Merino Wool 13percent Nylon Core Application: Layering Casual Apparel Weight: Lightweight Sleeve Type: Short Sleeve Features of Smartwool Merino 150 Baselayer Short Sleeve - Men's Slim Fit Our lightest weight Merino jersey fabric uses a nylon core to increase durability while still keeping 100percent Merino wool next to skin Offset shoulder and side seams designed to increase comfort and minimize chafing while wearing a backpack Side seams wrap to front for body-enhancing fit Flatlock seam construction designed to minimize chafing UPF 20+ Black Marble Wash Light Woodsmoke and Indigo Blue colorways feature plant-based dye technique Package Contents: Smartwool Merino 150 Baselayer Short Sleeve - Men's Smartwool SW000744545M: Merino 150 Baselayer Short Sleeve - Men's Light Gray Heather Medium Smartwool SW000744545L: Merino 150 Baselayer Short Sleeve - Men's Light Gray Heather Large Smartwool SW000744545S: Merino 150 Baselayer Short Sleeve - Men's Light Gray Heather Small Smartwool SW000744D36L: Merino 150 Baselayer Short Sleeve - Men's Iron Heather Large Smartwool SW000744001M: Merino 150 Baselayer Short Sleeve - Men's Black Medium Smartwool SW000744001S: Merino 150 Baselayer Short Sleeve - Men's Black Small Smartwool SW000744D36S: Merino 150 Baselayer Short Sleeve - Men's Iron Heather Small Smartwool SW000744D36XL: Merino 150 Baselayer Short Sleeve - Men's Iron Heather Extra Large Smartwool SW000744001XL: Merino 150 Baselayer Short Sleeve - Men's Black Extra Large Smartwool SW000744001XXL: Merino 150 Baselayer Short Sleeve - Men's Black 2XL Smartwool SW000744545XL: Merino 150 Baselayer Short Sleeve - Men's Light Gray Heather Extra Large Smartwool SW000744545XXL: Merino 150 Baselayer Short Sleeve - Men's Light Gray Heather 2XL Smartwool SW000744001L: Merino 150 Baselayer Short Sleeve - Men's Black Large Smartwool SW000744D36M: Merino 150 Baselayer Short Sleeve - Men's Iron Heather Medium Smartwool SW000744545XL: Merino 150 Baselayer Short Sleeve - Men's Light Gray Heather Extra Large