This is a A-661000 Belleville Spring, Red Marking PN: 661000Main Description As Following : A-661000 Belleville Spring; Red Marking P.N: 661000 A-661000 Belleville Spring; Red Marking P.N: 661000 Stocked As: A-W043489 Found in Section & Models : Driveline (by application) > Driveline Components, Massey Ferguson MOWER CONDITIONER: 164 (SN DZ000427C>), Massey Ferguson MOWER CONDITIONER: 166 (SN DZ000427C>) Associated Items : New Also This is An Aftermarket Product And : High Quality Afternaket Shipped from Both US and Canada