The Folding J Style Kayak vehiclerier is designed to transport your kayak or canoe on the side to save space allowing for a second watercraft to be mounted on the other side of your roof racks dependant on the length of your crossbars. Attached to a S512X extension piece, it is possible to vehiclery up to 4 kayaks or canoes on your roof racks depending on the length of your crossbars.