I had shown this previously, but thought an update might be in order. Many years ago I had bought a nice lightweight non-slip-backed indoor/outdoor carpet at Home Depot, which I cut to shape for the back of my Insights and i-MiEVs and boat. Unfortunately when I needed to add carpet to my newest used-iMiEV's entire rear compartment, I had run out of this stuff and Home Depot no longer carries it. Purely by accident I found some at Costco a few months ago, and I bought a roll and I kept the label: It's called Clean Green Indooor/Outdoor Area Rug, but when I just now tried to look it up on the Costco website, it's not shown. Anyway, it's tough stuff and I'm extremely pleased with it and it has done a great job of protecting the rear seatbacks (in the down position) for years. The label says it's made of 100% post-consumer recycled plastic bottles and is antimicrobial, made by Foss Mfg. Co. in Hampton NH. http://eco-fi.com
. Velcro hooks stick to it and it easily cuts with scissors. I have no affiliation with this outfit. Even though I've carried some very heavy stuff back there, I haven't felt the need for a plywood underlayment as this carpet cushions and distributes the load a bit. Our normal mode is to keep the i-MiEV in station-wagon mode, with three Rubbermaid containers wedged into place. Groceries are carried into the house by simply grabbing a container.