The above is correct, they are offset & from eurocampers. I am selling because we are relocating across the US and will be selling our van.They are Sportscraft swivels. Very nice quality and 40 lbs each! eurocapers.com sells them. The one for the drivers seat is a bit of a pain to swivel as it bumps the steering wheel and is especially bad if you have the armrest. It is ok though and the passenger one is great.
I use a driver’s side on on my passenger seat to get the advantage of the offset to move it towards the door when swiveled. I really like that!
triggergolf is selling them at a great price! I don’t know him nor have any interest in the sale.