Medium Cargo Box for XBULL Carrier SystemMedium Cargo Box Aluminum Heavy Duty Rear Cargo Box for XBULL Carrier System Before installation, please ensure that the rear lights are not obstructed by the cargo box. If the rear lights are covered, additional rear light installation is required. Medium Large Capacity Storage Box: Specially designed for the XBULL rear carrier system, offering ample storage space for your gear. Adjustable Shelving: Flexible shelves with storage boxes inside the box