1994-2003 Polaris 400 Trail Blazer ATV Engine Piston Ring Kit Bore Size (mm): 84.44 Ring Kits Include Piston Rings Only - Piston Not Included Namura Piston Rings Fit Both Namura and OEM Pistons of the Same Bore Size Unless Otherwise Specified Compatibility: 1994-2003 Polaris 400 Trail Blazer