Video at Amazon.com View As can be seen in the video, does the product, what it should. The feet fit well through the existing openings, the ball is not too loud, nevertheless makes "exciting" sound, if he lights up, or not. The rails have rubber studs, characterized the whole does not fly while playing through the area and the blue "roofs" are removable - for thick or tollpatschigeren cats;) You need the rails by no means double order (otherwise they would indeed sell so), unless you want to just build an adventure playground, but individually it works also perfectly. Mr Weasley's happy and had to get out after establishing the rotation less than a minute. He is 22 months, so if older cats do not immediately enter the game a little tip: davorsetzen the cat and perform with your index fingers. Have fun with it :)