Just made my back exhaust tube.carbon inside,then carbon/kevlar hybrid outer shell.For the side comeing out into the hull, it was wrapped with standerd carbon again to match the inside of the hull and added strengh...for the clamps.Its in ruff form,and prob could stay that why cuz ur not going to see it,but im still going to doll it up .These are just quick pics,will take better shots when the suns up.