I bought this top for our NP trip in the summer to not get burned and has become one of my favorites for hiking in warm and cool weather. I wore it hiking the Narrows at Zion in August and stayed warm in the morning shade and icy water and cool as the sun peeked over the canyon. By the end, it was getting warm, but dipped the top in the water and it was perfect. I've also used it hiking in Northern California and it is nice for those in between days when the sun comes out, but may be cool in the morning.I like that it's a V neck so comfortable while exercising, but provides ample sun protection. I've had it almost a year and it has washed up well. For size reference I'm 5'8" and 150 lbs and bought a Large. I just wish it came in more colors!