Yep, fixed directly to the van.
I had a T5 with a multi/remio rail and didn’t have a pull out awning attached, but used it to attach a drive away awning which was excellent and it also kept the rain off to.
now our drive away awning attaches to the pull out awning however the rain did get behind the pull out awning so we had to devise away of blocking up the gap, which we have with black foam.