The Micro Performance T is made with a 3.8 weight Intera yarn which will keep you cooler in warm weather and warmer on cool days.  The perfect conduit to wear under an Evaporative Cooling vest.  The shirt has a sheer silky feel to it and packs up at 1/4 the size and weight of a cotton t-shirt, leaving you much more cargo space for other things. Prices are slightly higher on 2X and 3X sizes.  

Sound RIDER! Cleaning Tips:  When cleaning synthetics use a minimum of laundry products.  Their additives can clog fabric, inhibiting the wicking power of the fiber.  Never use scented detergents or bleach and never-never use dryer sheets or fabric softeners.  For the best results use a product designed specifically for cleaning synthetic base layers like Nikwax' BaseWash. Always wash your synthetics seperate from cotton garments.  This will keep cotton fibers out of the fabric and drastically reduce drying time by 50% or more.