I never know how my furbabies will like the things I buy for them. So I often buy just one. I put this up today... and this just happened....so I bought a 2nd one just now.  My Devon rex boy on top is um...12.5lbs and my poor girl is 7lbs. She will be happy when the 2ne one comes in, no doubt! Easy to install! Obviously decent size and holds very sturdy especially if you make sure one side goes into a stud in the wall. I think its worth the money for sure!