Shop by Brand Yamaha OutboardPiston/Piston Kit ; Piston Pin ; Piston Ring Back Piston Kit 664-11631-00/664-11631-01 STD Viewer:1415 OEM No. : 664-11631-00/664-11631-01-STD For YAMAHA Outboard 20, 25 HP You May Also Be Interested In Piston Kit 646-11631-01 STD Piston Ring 688-11610-00 STD Impeller 775518/0775518 Piston Kit 783-9613A3/9613A 3 0.030