Durable Structure: Made of natural fir wood with healthy painting. Removable tray: one plastic pull-out tray can be easily removed to clean the second floor of rest zone no leak or rust. Easy to assemble with pre-drilled holes with the detailed instructions. Large Ground Activity Space: The stairs and platform allow the 2 bunnies to quickly enter the up and down through the staircase. Open-able asphalt roof: It not only can easy to open the roof to dry the rest zone from time to time but also can be used outside to protect the pet from rains.