Thats coroplast, but I would NOT buy that. Go to a sign shop and get a 4x8 foot sheet for half the price.
I bought my 4x8 sheets of coroplast from a plastics company in OKC for $10/sheet. Regal Plastic - Sheet, Rod and Tube Plastics Distributor Home Depot wants to empty your pocketbook!!! Besides that, 24"x18" sheets will drive you nuts trying to cover the entire belly.
It's not that home depot is "charging too much". It' a retail item for specific needs. (small) Since everyone is able to buy from a sign 'wholesaler' it makes better sense to find one. Sometimes though, finding one can be difficult and you have to go with a local source like home depot or lowes
__________________ MetroMPG: "Get the MPG gauge - it turns driving into a fuel & money saving game."