Double cocked board: the board surface commonly used maple, the board ends up, the wheels are hard and small, can do a lot of cool tricks, high flexibility, this kind of skateboard recommended for boys. The board has a concave surface, also known as the "footwell", the head and tail of the footwell a deep and shallow, deep good buckle board, shallow good control. Pros: Can do a lot of cool moves. Disadvantages: The wheels are hard and easy to shock your feet.