Hi guys I buyed the skybag 6 months ago. I thought the bag was fully waterproof but it was not. when it rained the water was went inside of the bag and my school books were spoiled because of the bag. And when I saw the ad of the bag I thought it will be very smooth if I wear it. but it was not smooth at all when I use it. Actually the bag has very low space. now I am at the collage my books are big and more than school I don’t think this is good bag for adultsThe main reason I don’t like this because it doesn’t have three zips or moreBut the quality is goodMaterial also fineThe bottle side is not good at allAnd through if there are too many books its so tight to wear itI can’t use one strip on itAlthrough this will cost too muchI recommend that buy another cheap and best bag than it