"Secure and transport a single kayak on a vehicle's roof without requiring side rails or cross bars with an Elevate Outdoor kayak carrier kit. Each kit includes a pair of 3.125"" by 15.75"" by 4"" foam blocks with an angled profile that compresses to fit a most kayak hull shapes and create a buffer between the vehicle roof and kayak. Includes two pair of cam buckle tie-down straps and two tie ropes for bow and stern securing. One pair of the cam buckle straps attach to the vehicle, the other pair to the kayak, and the tie ropes connect the two together. Foam blocks are made with high-density polyethylene foam for a firm grip to the vehicle roof and kayak."