My post just below this links to a page that shows my homemade seat. It's .125" ABS Plastic with 1" padding. The photo does not show the cord that wraps behind to support it. The nice thing is it is real easy to lean foward, just grab and pull!
: I followed Jay Babina's advice when building his Outer Island -- I used
: Yakima footbraces and a Rapid Pulse backband. Next time, instead of
: footpegs, I will probably just put foam up against the foreward bulkhead
: for foot support. This is more comfortable and does not require holes in
: the hull, but does not make the kayak easy for others to use. More
: importantly than the footpegs, though, is the backband. I don't like the
: way the R.P. backband can get kind of folded over as you enter the kayak,
: requiring that you do some adjustment before snapping on the spray skirt.
: Next time I will probably just fill the area behind the seat with minicell
: foam sculpted to my backside.

: Moral of the story: go with foam -- no moving parts -- simple is more
: reliable.

: Dean