The part that attaches the back to the bottom of the chair is flat. Since the seat is slightly curved, I was unable to get the 2nd screw in to attach the right side to the chair bottom, so not a good fit. The attachment needs to be slightly curved in order to screw to the seat bottom. I will keep the chair as it is comfortable and otherwise everything works. Just hoping that the lack of the single screw doesn't negatively impact the chair.UPDATE 6/30After some mis-communication issues between the seller and I (emails getting lost) the seller worked to get me a new chair. The seller promptly tried to contact me following my initial complaints but wasn't able to reach me. After this the seller was very helpful and sorry for my troubles. I commend the seller on this and would suggest buying from this seller with confidence.As for the chair itself overall it's a good chair and the thing I like the most about it are the ergonomics. My previous chair was giving me back pain while working and was starting to become unbearable which led me to buying this chair. The most important thing that separates this chair from others is the adjustable lumbar support. This is often the biggest point of pain for many people that this chair solves well. Additionally the chair tilts to give a little more wiggle room while you are working or doing whatever. All in all, I would give this chair a 4.5 if I could bit I have to deduct some points for the armrest (although good that they swivel) are positioned somewhat higher than i would like and the initial quality issue.INITIAL REVIEW:The headline sums up my experience of this chair. Looks like there are quality control issues around the seat cushions. Too bad I had already assembled the chair before I sat down to notice it. Now if I wanted to sit sideways 10 hours a day and hurt my back this would be fine, BUT I bought this chair to be able to sit comfortably while I work from home. My previous chair at a much cheaper price point (~$50) does not have any quality control issues, so it is odd to see a lack of quality at three times that price point. Do yourself a favor and DON'T purchase this chair. The seller will not work with you on issues with the chair. There are some other chairs at this price point that are more reliable.The chair is comfortable, sturdy and has a lot of great features, as the height adjustment, flip up arms and back support. It rolls nicely and swivels as well. While overall it was easy enough to put together, I did have trouble both with attaching the arms and the seat. Having another person to hold the item in place probably would have made it easier. Lining up the holes in the seat and the frame was another matter. I finally realized I had to loosen the arms so there was some adjustment with the alignment of the screws to be able to attach the seat properly.My biggest complaint is with Amazon. I ordered this on a Friday, received it on Tuesday, which was great customer service. A day or so later I realized the price had dropped $20 and it had a larger coupon currently. I contacted Amazon to see if I could get a credit since it was less than a week since I had purchased it and was told NO, they don't do that. I know I have had price adjustments in the past on similiar items and was disappointed that Amazon would not give me a credit since I am a Prime Member and order items all the time from them. Usually I am very pleased with Amazon's customer service but this time I feel they dropped the ball.The chair was easy to assemble. Took about 15 minutes.It has good support even when leaning back in it. I was using a cheap Walmart chair that had pretty much gave up on supporting my back and the arm rests were so uncomfortable and hurt my elbows.This chair has great support and the arm rests are comfortably padded and even fold up and down which is a plus since I tend to change positions after gaming for a long time.Overall I'm really happy with this chair for the price. I'm 5'7 and weigh about 150lbs and the chair seems really well adjusted for my body.i have only had it for a few days but so far I like it except back is too far away for real lumbar support.Good for the price -when available. The back is supportive and breathable.CONS:Seat is not tilt adjustable. Few chairs at this price are. I was able to 'shim' it back a few degrees on assembly.Seat does not breathe at all. You will get a sweaty bottom! It's a comfortable chair when I keep a folded towel on the seat.I’m so happy I got this chair. It replaced a chair I bought for my small work from home area in my bedroom (the old chair wasn’t supportive enough and was causing leg, hip, and lower back pain). My desk is in a super small space so at first I was worried this chair would be too big, but it actually works perfectly. It’s much easier to get in and out of my desk now thanks to the flip up arms. The seat pan is really comfortable. I have issues with leg pain and poor circulation if the seat isn’t supportive enough and sloped properly in the front. I’ve had no leg pain since getting this chair which is super rare for me, so I’m very happy about that. The back is also really comfortable and gives just the right amount of back support. The mesh is nice and cool as well. My hip and lower back pain are now gone thanks to this chair. A very large or tall person might need a bigger seat pan, but I think for the average person it would work great. I’m 5’5 140lbs and it’s a good size for me. I wish I had bought this one first and saved myself the $100 that I spent on the other chair. I definitely recommend it!Very satisfied with the chair. For me, all I cared about is if I sit on that chair for an hour, I won’t find myself shifting my weight from side to side or end up sitting in a pillow. I can sit on that chair for 8 hours straight and feel great. It looks good, it’s comfortable, nice setting on the different adjustments, and fair price. I really recommend this chair. I showed this chair to my one of my friends and they enjoyed it !We recieved this chair - it has 4 screws to attach the back to the chair. One of the holes was stripped so we used the other 3 to assemble the chair. The back support was awful and we had to remove it after a few visits to the chiropractor and then the line screw hole got stripped - probably from leaning back on only one... so now 3 months later the chair is completely destroyed.Height is easy to adjust and can pull close the desk for work for better support as arms can be lowered or pulled up.Easy to put together