Price not negotiable. Currently difficult to obtain or expensive even online. First come, first served. SKLZ SPEEDSAC PRO Speed Sack Pro Training, Leg Strength, Running Speed, Lower Body Training, Dash Heavy-duty specifications Weight: 4.5kg x 4 This is a short-distance running training device that allows you to change the weight. It trains explosive leg strength and speed. You can strengthen your lower body, focusing on leg strength and core, through resistance training. The weight is adjustable. [Condition] The box is damaged, but it has been stored unused. It will be packed in its original box with stretch film and shipped.