I created this shelter in haste for an approaching snow storm last winter. It's an old covered litter box. I lined the inside with mylar sticky pipe insulation and filled it with hay. I made 2 more like this out of litter boxes. They used it alot in winter when it was freezing, but I rarely see anyone in it anymore, so it made me happy when I came out and saw Mav was using it. :-) Is he not just the cutest???