Shop by Brand Yamaha OutboardPiston/Piston Kit ; Piston Pin ; Piston Ring Back Piston Ring 66T-11603-00 STD Viewer:712 OEM No. : 66T-11603-00-STD For YAMAHA Outboard 40 HP You May Also Be Interested In Piston Ring 6H4-11610-20-00 0.50 Piston Kit 6R5-11631-11 STD Bolt 90109-09M60-00 Plate 679-45321-02-00