a system for retraction and deployment of a covering over at least a portion of a vehicle interior is disclosed , such as might be employed in commercial or sport utility style vehicles to provide a convertible hardtop over a portion of the vehicle that can be retracted for open air and ease of access , or closed for physical and environmental protection . the system provides : first and second roof panels ; first and second sidewall panels ; and posterior and anterior roll bars , each roll bar having at least one channel whereby the first and second roof panels and the first and second sidewall panels are guided between a deployed position and a stowed position , such that when the panels are in the deployed position the vehicle is enclosed and when the panels are in a stowed position the vehicle is at least partially open .