87121-ZY6-C00 RR (150) Mark - Overview. The 87121-ZY6-C00 RR (150) Mark is a genuine Honda OEM part designed specifically for the marine marking system on Honda marine engines. Serving an identification role within the rigging and accessories system, this mark is essential for proper labeling, ensuring accurate identification and easy maintenance tracking of the engine component. Designed to integrate cleanly with existing parts, it ensures seamless operation and durability in Honda marine engin