RJ Classics Sienna Jr. 37.5 Training Shirt


We love this sun shirt for it's bright colors and patterns paired with the top of the line cooling benefits. A perfect top for when you're schooling ponies all summer long.

The Sienna Jr. with 37.5® technology is the perfect schooling style for even our youngest of R.J. Riders. 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!).

Some colorways feature a unique patterned mesh, while others feature a tonal mesh.

  • 37.5® thermoregulation technology
  • Main body fabric has UPF 50 sun protection
  • Mesh underarm panels