The ROP Shop Centrifugal Clutch 3/4" Bore, 10 Teeth for Mini Bike with #40, 41, 420 Chain. Please review all product information to ensure that this product is compatible with your unit. Our staff constantly strives to provide clear and concise product information. We understand that sometimes it can be difficult to confirm product compatibility. It is your responsibility to confirm this is the correct product you need; therefore, we encourage all customers to fully review the information provided in this listing prior to purchase. Nothing is worse than having to return a product, trust us...we get it. Let's work together to avoid this! If you are unsure as to whether or not this is the correct product for your unit, please ask. If you seek assistance we will need as much of the following information as possible, if applicable, to help you find the product you are looking for: ▪ Model and/or Sub-model ▪ Spec and/or Type Number ▪ Code and/or Serial Number ▪ Year ▪ Engine Horsepower. Our knowledgeable product specialists are always willing to help you verify product fitment. Stay rugged, my friend.