This Ellie-Bo divider is designed to fit an extra large Ellie-Bo cage measuring 42" long x 28" wide x 31" high. It reduces the internal size of the cage. Please note, this divider is not intended for dividing a cage for multiple occupants. It is easy to install. Once installed, there will be space underneath the divider to accommodate an Ellie-Bo cage bed that runs the full length of the cage, eliminating the need to purchase additional smaller bedding.