Thanks to the Yakima HullyRollers, you no longer need a crane or the neighbors to help you load your kayak. The HullyRollers make it simple to slide your boat onto your car's roof. Simply place the bow or stern of your kayak onto the U shaped pair of rollers and push your boat on up there the Dynaflex rollers pivot for convenient loading angles. You need the Yakima Mako Saddles sold separately to complete this safe, secure, and simple boat transporting package. To bolster stability, Yakima threw in a heavy duty strap with padded buckles and a pair of bowstern tie down straps. The HullyRollers fit square and round crossbars and work with factory crossbars with MightyMounts sold separately.