These load-assist wonders will enable you to sling your boat onto your roof like you're a circus strong man. Comes with all the hardware you need to secure your boat with a kung-fu grip. Form-fitting cradle fits most hull shapes. Dynaflex grips provide a snug grip when you tighten the straps. Aero version fits round, square and factory crossbars out of the box. Standard version fits round and square crossbars.