Elegant, easy-wearing, and essential in chilly climates! This body-hugging long sleeve shirt is perfect for layering on cold days. Help your body relax, feel warm and improve circulation in winter weather with our special therapeutic textiles. *This tends to run snug as a base layer, size one up if you want a little more of a casual fit* What are Back on Track Infrared Textiles? Infrared textiles are just that – a textile using technology that recycles infrared and visible light into energy. When placed near the body, this energy is redirected back to the body, increasing blood flow and oxygen levels of local body tissues The increased tissue perfusion of oxygen can help joints and muscles fight stiffness, soreness and swelling caused by aging, injury, or arthritis. Products containing our Welltex technology were designed to: -Enhance tissue oxygen levels in the body -Stimulate quicker recovery and healing -Heighten strength and athletic performance -Suitable for pain or stiffness around shoulders and shoulder blades and upper back, neck and arms. -Cotton / polyester -Large: 40 XXXL 46https://botcanada.com/ Sizing charts can be found https://botcanada.com/sizing-charts/