From inside (document excerpt):
PARTS LIST NO. DATE 545103487 Replaces 545103487 — 5/28/08 r PARTS LIST Note: Illustration may differ from actual model due to design changes CHAIN SAW MODEL(s) Mac 4- 18XT PAGE NO. 6/09/09 1 28 42 41 39 40 WARNING All repairs, adjustments and maintenance not described in the Operator’s Manual must be 27 26 38 37 36 performed by qualified service personnel. Description Diffuser Muffler Screen Spark Bolt Muffler Grommet Throttle Cable Kit Carburetor (WT 891) (Incl. Grommet) Gasket Carb. (kit) Screw Carb. Adapter Screw Gasket Adaptor(kit) Ring Piston Retainer Piston Pin Kit Piston (Incl. 31 & 32) Kit Engine Gasket (Incl. 20, 26 & 30) Scrench Assy Seal & Bearing Cap Crankcase Ref. 38. 39. Part No. 530047062 530047207 Description Assy Crankshaft Assy Muffler (Incl. 19,20,21,22,23) Not Shown –n 545177363 545167627 545167628 545167629 545167630 545167631 545167632 545167633 545003025 545003009 Manual (Scan) ( Euro 1 ) ( Euro 2 ) ( Euro 3 ) ( Euro 4 ) ( Euro 5 ) ( Russian ) ( Turkish ) Decal Warning CE Decal Warning n = NEW PART NUMBER FOR THIS K = REFER TO THE SERVICE REFERENCE INDICATED FOR MORE INFORMATION. (LOCATED AT END OF IPL)