WISCO replacement ring set (LK)LK type consists of one top ring and one compression ring:* Top ring: Nodular iron semi-keystone "L" shape.* Compression ring: Chrome-faced high temp steel alloy with ferrox coating.Please note: Only WISCO replacement ring sets may be used onWISCO pistons. The ring type and bore size (mm) is stampedon the dome of the piston. Refer to this information to orderthe correct replacement rings. Ring styles cannot beinterchanged.