Filson's Thermal Crew is made with a Peruvian cotton blend in a waffle-knit pattern with deep channels to trap body heat. Provides superior insulation, air circulation and breathability. Ideal as a stand-alone shirt or as a base layer in cold weather. | Filson Waffle Knit Thermal Crew Charcoal Size XL Merino Wool Ribbed Crew Neck Top, Ribbed Merino Wool Crew Neck Top, Wool Knit Crew Neck Tops, Ribbed Merino Wool Tops For Layering, Wool Crew Neck Tops For Layering, Fall Layering Henley With Crew Neck, Ribbed Crew Tops For Winter, Merino Wool Tops With Ribbed Cuffs For Layering, Knit Crew Tops With Ribbed Cuffs