This cage is large. No mistake about that. I have three boy rats this cage is perfect for them, a wheel, a house and the hanging pirate ship, hammock and tunnel I have for them. Its not the easiest thing to put together so make sure you have another person to help you, and a mallet handy. My friend and I were able to put it up in about 15-20 minutes.
The bar spacing is great for these little guys as well. My littlest rat was escaping through the bars of their old cage which is why I needed to purchase this one. you might want a scatter guard since the walls of the plastic tray are about an inch tall. I use cardboard to line the inside and it work well enough. Overall im very happy with this cage and so are the boys! (Just be careful with the doors when you close them as its easy to get their tails caught in them.)