We made this shirt specifically for warmer days, with a mesh fabric on the front that allows plenty of air to pass through to cool you, while on the back we have created a fabric that while being breathable and super light, blocks out over 9% of ultraviolet rays, but don't consider it a top to wear only on the hottest days. Add an underwear and you can wear it from mid-spring to early autumn, the elasticity of the fabrics will make its fit perfect and you will see how it is extremely comfortable.