9807B-5617C S/Plg (Izfr6k-11e) - Overview. The 9807B-5617C S/Plg (IZFR6K-11E) is a genuine Honda spark plug designed for use within Honda marine engine systems. It serves a critical function in ignition, supporting efficient combustion and reliable engine starts in selected marine engines ranging from 75hp to 250hp. Intended for Honda outboards, this spark plug maintains engine performance and smooth operation by delivering precise and consistent ignition.. Key Features. OEM genuine Honda spark