Two-story travel comes standard on this 4-in-1 pet stroller: each of the two detachable fabric carriers works as a carriage bag, travel crate, or car seat carrier, giving both pets a private 13 x 14 x 22.5 inch cabin. The frame folds in about 3 seconds, thickened Eva wheels absorb curb shocks with 360 degree front swivel and rear brakes, and mesh windows keep air moving on every outing.