Sleeping in Swamp Thing!
The sleeping bag came out in the early 90s along with all the other collectibles from the cartoon series. The stock illustration used by most of the marketed materials appears to be colored differently for the sleeping bag. ST appears to be wearing some sort of vine singlet. I wonder if the marketing folks felt that Swampy needed swamp trousers to be deemed appropriate for kids to sleep in.
Although it is a bit small for adults, you can unzip the bag to make it a blanket for all of your house guests to enjoy and drool over.