This is in between a L/S jersey and light jacket. I wear this with only a sports bra underneath in 55-65 degree weather and it works great. It is not scratchy at all, so no base layer needed if weather is cool. Lower temps, I would wear one. It is long in back and, thank you,.... longer in the front as well! Also, nice long arms. It is white in front and black in the back. I have good movement all over, but I did order up a size, should I need to layer more and it is not cold enough for my winter jacket (Castelli Inspirazione jacket... amazing, by the way). Good for some wind protection, but not great. I have had to unzip on climbs. I am 5'-8" weigh 135 (140 in winter), got a Large, and glad I did. Plenty of room but not oversized in the mid-section for me at all. Overall - a great jersey for cool weather.