Anyone have a Chariot Cougar (child trailer)?

I emailed Chariot with this question a week ago, no reply, GRRRRRRRrrr

How much cargo space does it have in the back? It's described as only
"2 grocery bags" worth. We can wedge an Aluminum frame baby backpack
in the back of our Koolstop trailer, but at the bottom you could say it
only has space for 2 full grocery bags, too...

I'd really like an answer in litres...?

TIA -julii

Oops, forgot to say! It's the Cougar 2 (for 2 children) I'm intrested
in. Ta -j