A key first defense from the chill. The Fox Racing Frequency Sleeveless Base Layer Jersey offers a fitted design and is made from a polyester fabric to provide the ultimate base layer in your cold weather arsenal. Fitted under layer garment keeps you comfortable without weighing you down. Wicking polyester fabric pulls moisture away from your skin to keep you dry and comfortable. Flatlock constructed seams to help prevent chafing in critical areas. 4-way stretch fabric improves mobility while maintaining shape.