Yes, this jacket does run maybe a size small, so you should size up, 2 sizes up would probably give a lot of extra room for air, but one size up works. The jacket blows are around inside (and into the hood when you put that up). I got it so that I wouldn't get sweaty on my bike rides to work in the morning. This probably won't be super effective in 100 degree weather since it is just blowing around air ad doesn't have a cooling ability, but was good today in the mid/upper 80s. Just sit in a hot room with a fan on and that is the effect you can expect. It certainly makes more days tolerable as outdoor days. It is a bit annoying that the battery pack is a separate purchase, but other than that, their photos are 100% accurate and it does what it says it does. I will update this in the summer to let y'all know how it does in real heat.It does do as advertised but the 2XL is more somewhere between a large and XL while the XL is more of a large medium. If you are tall it's not long enough and if you have a couple extra pounds the air probably won't circulate well. Same with weighing down pockets with things, too much weight in the pockets prevents the air from circulating around your upper body. If you are a small person and don't have much to carry then don't miss out it's pretty good. If you aren't so little one way or another, might want to give it a pass.While the weather has not allowed me to use the jacket in a high heat environment yet I was pleased to find out that my 18V Makita batteries when combined with the Makita cell phone adapter accepts the Jacket USB connector and allows the user to fully utilize the green three speed control unit that comes with the Jacket. The Makita adapter has a belt clip to distribute the weight so this potential problem with a light weight jacket is eliminated. I re-routed the USB connector from the Jacket pocket to the Makita Battery/adapter combo which clips to my belt under the jacket. Another advantage is that the fan locations on the back of the Jacket are such that you can wear it while operating equipment with a seat back. This is not always the case with other brands.I wear a XLarge shirt and ordered the XXLarge Jacket which fits but with not much room to spare. Will update this review after I have had the chance to use the Jacket in a high heat environment.I purchased this jacket before Our latest camping trip this weekend. It has been very hot here in Illinois, and our camping area was secluded with trees surrounding us, so there was no breeze at times. The other guys were miserable in the afternoon/evening, I had my jacket on, and it’s like being in a breeze whole time time!! Just the fact that the air is moving over your torso, is enough to keep you cool!! I never would have thought it would work so good, but it did! I let two of my smaller friends try it on and they both loved it.One of my friends actually ordered one for himself when we got back into cell phone range. I would highly recommend this jacket, it does what it says it does, and well worth the money!Works as described. Best purchase in a long time.I was experimenting with this vest when I'm out working on my bee hives and while the vest is definitely cooling my body, I didn't get quite enough airflow on my arms and they got sweaty pretty quick. For the price I still think it's a good deal but I would rather spend more money on one with more powerful fans.This jacket works pretty well. I wear a huge plastic custom fitted brace that gets very hot (since it is summer). This jacket does keep me much cooler. You just have to keep it zipped up all the way. I lookIike a big puff ball, but I don’t care!*** UPDATE ***Jacket and fans have been working great! Great way to keep cool. Bumped from 4 to 5 stars ;)- Original reviewPurchased this to see if it will help keep me cool during hot weather. The fans are easy to remove for washing the jacket. The air rises and exits around the neckline when the jacket is zipped up so you get a breeze around your face. You'll need to supply your own USB battery pack to power up the fans. I use a USB extension cable so that I can keep the battery pack in my pants pocket instead of in the jacket. Looking forward to trying it out on some hikes or when I am out flying my drone.