"This set is a fun way to organize keys for kids. We have chosen to have single keys on both the Lego key chains and on the hooks on this set. It works wonderful when the chaotic boys needs the key to the work shed to get their toys. The back is quite solid, even though it is cardboard. It also makes it easy to mount inside a closet. Ours have been hanging with keys for almost 8 months with no damage. And even though you only get 1 Lego key chain, this makes it more fun to choose which colors to buy (even if I was shouted down when I tried to suggest a pink one..). Teaching our kids responsibility when it comes to keys is important, and a lot easier with this fun Key Chain Rack."