skinned in 2/2 twill carbon fiber,interior skinned in carbon fiber/kevlar,didn't build the boat for maximum speed/competitive racing, just for fun. With the high price of scale drivers I opted for a couple of my sons 'spare' action men cut in half just below the chest and fitted with small steel angle brackets,bolts and nyloc nuts. (Motor: zenoah G260pum marine) (10/10)