It's just a tiny O-ring, but oh boy can it cause big problems if it fails! This 9.8mm x 1.9mm O-ring replaces several Honda part numbers including 16075-P07-000, 91303-729-720, and 91305-PE2-003. Also fits other OEM numbers like 37830-P05-A01. From NMD, MPN OR9.8X1.9. Brand new in original packaging. Perfect for various Honda applications where you need a specific size sealing ring. We're talking engine components, fuel systems, or anywhere Honda used this particular dimension. Leaks are annoying (and sometimes dangerous), and replacing a worn O-ring is often the simple fix. Keep a few of these on hand if you work on Hondas regularly - they're cheap insurance against leaks. Installation is easy if you have access to the component (sometimes the hard part!). Just make sure surfaces are clean, lubricate the O-ring slightly, and press it into place. Stop that drip before it becomes a bigger issue!