Complete Catalog (PDF) CouplersAxles, Couplers, Trucks, Wheels Monarch Couplers, Bottom-Operating (1 pair) PN#3818 CouplersAxles, Couplers, Trucks, Wheels Monarch Couplers, Top-Operating (1 pair) PN#3817 CouplersAxles, Couplers, Trucks, Wheels Monarch Couplers, Non-Operating (dummy) (1 pair) PN#3816