He can go in the third floor and climb in the tube to the fourth floor or do the opposite around. He likes to play in the tube especially I am at the other end calling his name.
The tunnel is not really made of metal but something like wire covered by thick aluminum foil. It is flexible so we can change shape and readjust the ends of the pipe so that the edges are smooth. For some reasons Coffee has no problems climbing up and down the pipe with enough traction. I bought the tunnel from City Mill. I think it was originally purposed as the air conditioner pipe.