This is a A-SK368 Piston Liner Kit PN: SK368Main Description As Following : A-SK368 Piston Liner Kit P.N: SK368 Overbore 3-3/8" To 3-7/16"w/ stepped head piston Replaces: A-PA321 IH , Crossed From: PK156 , , 141428 , Found in Section & Models : Engine Parts > C152 CID, Case-IH TRACTOR: HV (SN <108970), Case-IH TRACTOR: OS4 (SN <33339), Case-IH TRACTOR: OS4 (SN 33340>), Case-IH TRACTOR: O4 (SN <33339), Case-IH TRACTOR: O4 (SN 33340>), Case-IH TRACTOR: W4 (SN <33339), Case-IH TRACTOR: W4 (SN 33340>) Associated Items : New Also A-IH-O-H, A-IH-O-H1948, A-IH-P-ACCESSORY, A-IH-P-HHV, A-IH-S-HHV, A-MAG-S-317, A-IH-O-O4OS4, A-IH-P-ACCESSORY, A-IH-P-O4OS4W4, A-IH-S-HHV, A-IH-O-O4OS4, A-IH-P-ACCESSORY, A-IH-P-O4OS4W4, A-IH-S-HHV, A-FRM-IHOL, A-IH-O-W4, A-IH-P-ACCESSORY, A-IH-P-O4OS4W4, A-IH-P-SUPERW4, A-IH-S-HHV And : Overbore 3-3/8" To 3-7/16" w/ stepped head piston