The 12,000 lbs. Pulley Block Assembly is engineered for the KWSL2000RM, KT2000, KT3000, KT4000 and all KU Winches. The 12,000 lbs. Pulley Block allows the winch user to double the pulling capacity of his winch. The 12,000 lbs. Pulley Block also has a clevis hook with safety latch build in to make setup more efficient.