Non air mattress bed pads?

Need a softer bed pad than just my bed mat for hanging out in the back of the taco. I found this pic of a green foam-looking pad in the back of a second gen, can't find anything else on it.

Does anyone know anything about this?

 

Looks like an old wrestling mat

 

Those look like repurposed gym mats.

I sometimes chill back there, so just toss in one of that I already have. They’re a bit pricey but we already use them for climbing, so they’re “free.” They all have backpack loops and some buckle into a little recliner shape.