56110-ZW4-H12 Piston Rod - Overview. The 56110-ZW4-H12 Piston Rod is an essential component in Honda marine engine systems. It plays a critical role in connecting the piston to the crankshaft, converting the piston's linear motion into rotational motion that drives the propeller. Designed for Honda's marine engines, particularly in the Active Marine series, this piston rod ensures reliable and efficient engine operation. Engineered to exact factory specifications, it fits perfectly with existing