"These tubes are awesome, I love how my hamsters have extra room to run around.
The blue look-out area has air-holes underneath it, so crumbs and food would always slip through and make a mess, so caution.
They are also REALLY hard to take apart; they're connected SO tightly by the rings, it hurts my fingers to pry them apart. I avoid cleaning them as much as I can; I try to make my boyfriend rip them apart for me whenever he is around, ha.
Also, be careful taking them out of the hole in the cage; the plastic parts on hole (on the cage) made for these tubes to connect to can be broken off."