The Carrera 3/30 High Banked Curve Outside Shoulders increase the width of the track and come in a six pack along with two straight end shoulders (1 - right side and 1 - left side), and each shoulder is 3.90 inches wide. This 3/30 High Banked Curve Outside Shoulder is made to fit on the outside of the Carrera 3/30 high banked curve. 1 piece = 30 degrees, and 6 pieces = 180 degrees (half circle).