Shop by Brand Yamaha OutboardPiston/Piston Kit ; Piston Pin ; Piston Ring Back Piston Kit 664-11635-00 0.25 Viewer:1340 OEM No. : 664-11635-00-0.25 For YAMAHA Outboard 20, 25 HP You May Also Be Interested In Piston Ring 64D-11605-00-00 0.50 Piston Kit 646-11631-01 STD Propeller 648-45941-01-36 Oil Seal, SD-Type 93102-36M33-00