Polaris 2879977 Cab Extender Use this versatile extender / divider to securely extend the usable cargo area beyond the rear of the cargo box, or to divide the cargo box and keep cargo separated. This extender / divider allows you to securely carry oversized items and also to keep varied materials separated in the cargo box.Can extend the usable area of the rear cargo box beyond the tailgate.And can divide the cargo box to securely hold varied mat (each sold separately).