[donv]

Further mod I plan on this is to upgrade the installation by placing a thick-ish plastic sheet behind the bladder in the seat. The bladder slips in between the seat springs and the cushion. I'm concerned that over time the spring may abrade the bladder and cause a leak. A flat piece cut out of the side of a washer fluid, bleach, etc. bottle would probably do the trick. Thick enough to protect but not stiff enough to affect seating comfort.