The RefrigiWear Iron-Tuff Vest is perfect for extra warmth in the winter or colder environments. It features a longer back for extra warmth, stretch knit side gussets for snug fit, insulated knit collar and hand warmer pockets. The vest's nylon outershell provides tear and abrasion-resistance and helps to seal out the wind and cold.Sizing Instructions: For the most accurate fit, take your measurements over the base layer of clothing you intend to wear with this RefrigiWear gear (such as thermal underwear, jeans or a sweatshirt) and refer to the size chart for this product.