The key to staying comfortable on cold days is staying dry. The Pearl Izumi Men’s Long Sleeve Base Layer uses a construction method called plating to place recycled polyester technical fibers next to skin on our responsibly sourced Merino wool, long-sleeve base layer. By putting polyester next to the rider’s skin, it transports moisture away to the Merino layer where it can evaporate even as the wool acts as insulation. The base layer uses a set-in sleeve design for a versatile form-following fit to make layering easy. The Pearl Izumi Men’s Merino Long Sleeve Base Layer is offered in the color black and is available in multiple sizes. Please refer to the attached size chart to help determine the best size for you.