New, unused urethane rubber, 1 piece. ◎ Replacement urethane rubber for Neil Pryde (current type, Euro pin/US cup) joint base. ◎ Replacement urethane rubber for Alone joint base. ◎ North (old type) can be replaced. Neil, Alone, North: can be replaced with the same item. Uses urethane rubber with a hardness of 95. Used for sail sizes 4.5 to 7.2, twice a week for one year. The color darkens slightly, but it worked without any particular problems. We recommend early replacement, around twice a week for one year.