WISECO REPLACEMENT RING SET. ÿÿXGÿtypeÿsets consist ofÿTop Ring, Compression Ring, and Oil Ring. ÿ Top Ring: Chrome-faced high temperature steel alloy. ÿ Compression Ring: Taper-facedÿductile iron. ÿ Oil Ring: 3-piece low tension oil ring. ÿ The ring type and bore size (in mm) is stamped on the dome of the piston. ÿ Refer to this information to order the correct replacement rings. ÿ Ring styles cannot be interchanged. ÿPlease note: Only WISECO replacement ring sets may be used on WISECO pistons.