I actually cannot believe that I was asked to write a review for these, since they never arrived. Instead of these rails I received a photo canopy for small item photography and a large food warmer. Then in response to me contacting them to rectify the situation all i got was offers of partial refunds for the problem, and never once was there any indication or offer to send the correct items. I eventually just cancelled the order, got a full refund, and purchased these rails from a different source.
Now, it is evident that there is no human presence at Vevor as I was asked to write a review. These are not business oriented people, this is a warehouse pushing out stuff without any means to correct errors. If the same happened to you, do not settle, demand full refund.