R.J. Classics Ladies Sienna Training Top The Sienna schooling shirt with 37.5(R) technology gives ever rider that classic, yet sporty look that will never go out of style. The patented thermoregulation technology has proven to help your body manage its core temperature and therefore, increase stamina. It keeps you comfortable by helping your body to maintain an optimum core temperature of 37.5 Celsius (99.5 Fahrenheit) which is ideal for peak athletic performance. The particles are naturally derived and work for the life of the product (it will never wash out!). Features: 37.5(R) thermoregulation technology Main body fabric has UPF 50 sun protection Tonal mesh underarm panels Item Specifications: Material: 44% Polyester/44% 37.5(R) Polyester/12% Spandex Care Instructions: MACHINE WASH COLD SEPARATELY INSIDE OUT GENTLE CYCLE DO NOT USE BLEACH OR FABRIC SOFTENER LAY FLAT TO DRY COOL IRON BODY FABRIC IF NEEDED DO NOT IRON MESH DO NOT DRY CLEAN