1. Performance Engine Component: This largebore cylinder piston set is specifically designed for MS660 066 chainsaws, featuring a 56mm diameter with Nikasil coating for heat dissipation and reduced friction, resulting in enhanced performance and extended engine lifespan compared to standard parts. 2. Materials: Crafted from quality aluminum alloy and precisionengineered components, this replacement part offers exceptional durability and wear resistance, making it a reliable upgrade for your chainsaw to withstand demanding cutting conditions. 3. Complete Replacement Set: Each package includes a full cylinder assembly with all seals and components, as shown in the images, providing everything required for proper installation without the need for additional parts or accessories. 4. MultiModel Compatibility: This cylinder set is compatible with various chainsaw models, including 064, 066, MS640, MS650, and MS660, offering a versatile replacement option for professional woodcutting and forestry experts.