This Genuine Tohatsu Marine Part is a piston ring set that is designed specifically for Tohatsu outboard motors. It is an oversized set with a 0.5 O/S measurement, meaning it is slightly larger than the standard size to accommodate for wear and tear. The part number for this set is 3C1-87124-0. These piston rings are essential components in the engine's combustion chamber, providing a tight seal between the piston and cylinder wall to ensure optimal compression and power. Made with high-quality materials, this Genuine Tohatsu Marine Part guarantees durability and reliable performance for your marine engine.