Hose.
My 65' front split folding bench seat weighed a whopping 100 lbs complete with mounting brackets and all.
The A-100 seats with A-990 aluminum non adjustable brackets will be around 40 lbs complete for the pair.
You are looking at a 55-60 Lbs savings with that alone.
Hot rod magazine did an article about lightening up a Duster a while back.
The A100 van seats weighed 28 pounds each.
Split bench is 95 pounds, typical bench seat is 90.
Like i said, more like 30-35 pounds total weight loss with two seats and aluminum brackets over the bench