This is a A-21A807 Spark Plug PN: 21A807Main Description As Following : A-21A807 Spark Plug P.N: 21A807 Dim B (2): 14mm ThreadDim C (3): 7/16" ReachDim D (4): 13/16" Hex ShoulderDim E (5): Autolite 216 Stocked As: A-21A873 Found in Section & Models : Ignition & Electrical Parts > Ignition & Related Parts, Ford / New Holland (UNDEFINED): SEVERAL Associated Items : New Also A-FO-O-16-46COMB, A-FO-P-FERGIMP, A-FO-S-CONSUMPR And : Dim B (2): 14mm Thread Dim C (3): 7/16" Reach Dim D (4): 13/16" Hex Shoulder Dim E (5): Autolite 216