by American Motorcycle Specialties http://www.amspecialtiesusa.com/gelpad.htm
Bought this for the wife, she used it once, then bought her own bike and doesn't ride on the back anymore. This retails for $89.95 plus shipping. It is the Large neoprene covered pad. I bought this last summer, so it doesn't have the memory foam that the new ones have. It is in like new condition. The bottom is a waffle non-slip surface, so it doesn't move around on the seat. It's a nice pad for someone that needs it. I'm asking $60 shipped.

the top above ^, the underside below v