The loose fitting, thin material along with open back makes the isobar tee perfect for working out in hot environments. Personally, I’m a huge fan of the relaxed, droopy fit and the “Athleisure”- type style clothing that has become popular recently, so I enjoy wearing this to run errands as well. The open back and thin material are a great opportunity to subtly show off a cute sports bra, and again keep you very cool when working out. I also LOVE the English Manor color and the cut of the shirt looks great with pants or leggings (maybe try Mission’s System Leggings!)I like this top a lot. I bought the Mission Short Sleeve V-Neck T-Shirt in size Small. But with the review that this Isobar Top is quite big, I opted for XS for this one and it fits perfectly!! The opening in the back is quite big, but if you wear it with a good sport bra, the overall look is just very nice. For a reference, I am 5' 6" and 105-110 lbs. Overall, I am happy with this top.Ordered a size up and was still tighter then I like but it's a good quality shirtOnly if you are thin and in great shape should you order this top. It is extremely hot where I live, so I thought this would be great. It is only if you do not care what you look like! I definitely do not look like the picture!Very comfortable top, love the cutout on the back and the breathable fabric.You definitely want to emphasize having a really really good bra to wear under this. The opening in the back is nice for cooling and potentially even sexy, but you're doing to be able to see the sports bra easily, and if you happen to be a person who doesn't necessarily need a bra, you should note that the fabric is very thin and doesn't offer a lot of concealment. Definitely good for shedding sweat and heat, but thinner and closer to see-through than I was anticipating. It's probably also worth noting that you should be careful about going out in summer near noon, since the open back isn't exactly going to protect you from sunburns either (it's not exactly the easiest place to reach for sunscreen), but if you exercise early or late in the day that won't be a problem at all.Overall I still like it, because it focuses on doing the things it promised. The thinness is fine in darker colors and it seems like most lighting, but I suspect with the wrong lighting anything under it may be visible, so I'd probably just be careful to make sure I'm wearing something underneath I'm okay with people seeing if I'm out in public.This is true Lu and open back. I mistakenly thought there was a bar of cloth across the back from the photos in the ad, but no. What you are seeing must be her bra, because this back (see photo) is clearly open.The cross cross design dose keep it close to your body when running and exercising. I had originally thought my strong-bean daughter could try it out for volleyball, but it fits large compared to its stated size. I ordered a small, but I can wear it well-fitted, and most of my athletic shirts are mediums that I fit well into, not loosely.The fabric is cool and without a back you can sweat up a storm and cool off back there! Downside- make sure your running buddy gets sunscreen on that hard to reach area before you head out!I docked it a star for not being sized well, having a completely open back with somewhat false advertising, and for not being as comfortable as some of my Namebrand athletic cut shirts.I ordered this product for my teenage daughter who really liked it. She IS a runner, but wears it for running or for just the general good looks of it. It has a unique style to it (see picture of the reverse side of it for a better idea of what I mean by that) that sets it apart from more traditionally-styled running apparel. A small fit my 17-year-old daughter very well. She is about 5'6" and weighs about 115 lbs. She has received a lot of compliments on it while wearing it, which has boosted her overall opinion of it. If you're interested in something a bit different from the norm and are concerned about looking good while exercising, this may be worth while taking a closer look at.