Special Change Cylinder Head Wrench, Special Change Piston Wrench. Fit for follwing models, not only these models. ViO12 (ViO12-2A), ViO17 (ViO17-1), ViO20 (ViO20-6), ViO25 (ViO25-6A), ViO30 (ViO30-6B), ViO35 (ViO35-6B), ViO50 (ViO50-6B), ViO55 (ViO55-6B), ViO80 (ViO80-1), ViO82.