REPLACEMENT FOR Strings #25 or #25H || 2 Stroke 47cc 49cc Mini Quad Dirt Pit Bike Pocket Bike ATV 4 Wheel Scooter; SIZE Center Hole Diameter: 12mm/0.47"; Outer Diameter: 75mm/2.95"; Thickness: 17mm/0.67"; (As the picture shows) EASY TO INSTALLMade of iron. The material has high hardness and good toughness. The surface of the clutch is smooth, not easy to deform or fall off.The clutch is equipped with heat-treated hardened spring with composite lining, which has faster starting speed and faster response speed. NOTE Please check the model number and size before ordering to ensure this is the correct part for your engine. CUSTOMER SERVICEAlways available to help our customers.Please message us for replacement or refund if you are not satisfied with the order;Be happy Online in your time. REPLACEMENT FOR2 Stroke 47cc 49cc Mini Quad Dirt Pit Bike Pocket Bike ATV 4 Wheel Scooter; Made of iron. The material has high hardness and good toughness. The surface of the clutch is smooth, not easy to deform or fall off. The clutch is equipped with a heat-treated tempered spring with composite lining, which has faster starting speed and faster response speed. Using metal alloy, has excellent pressure resistance, can withstand harsh environments, reliable and wear-resistant Dynamic balance, shake goodbye, no slip, no noise, strong power, reduce damage, more comfortable to use. Specially designed wave mechanical spring, extend the time clutch aging, makes starting smoother, more uniform transmission of torque and revs between transmission and engine.