HIPA 49mm Big Bore Cylinder Piston Kits Assy for STIHL MS390 MS290 MS310 029 039 Chainsaw Pin (10 x 32) Circlip Ring Cylinder diameter: 49mm Fiment models: STIHL MS390 MS290 MS310 029 039 chainsaw Package include: 1pc cylinder, 1pc piston, 1pc pin, 2pcs psiton rings, 2pcs clips