Foam blocks are sold individually. A set of four is usually recommended for transporting your boat.
One cut out secures snuggly around the gunnels of your canoe. Universal gunnels will work with almost any gunnel style.
Canoe Blocks for naked roofs have a non-skid surface to prevent the block from sliding on top of your vehicle. Canoe Blocks for vehicles with aerodynamic or ovular cross bars have a second cutout to secure the block to your crossbar.