*Usually ships within 7 to 14 days.The BuckBlocks™ Climbing System was designed to ease climbing while reducing premature wear on climbing lines and eliminate damage to tree limbs that are normally caused by excess friction. The design is lightweight, provides a better bend radius for rope and an improved running surface with its dual rotating sheaves. The BuckBlocks™ Climbing System is designed to be used by an individual with a maximum weight of 350 lbs. when fully equipped. Sheave capacity: 1/2″ climbing rope.