<b>Important note 1: The pulling force of this chain is 750-780 kg, which is easy to break beyond this pulling force.</b><br><br> <b>Important Note 2: Please buy this chain from "Mumaxun Ltd", because it is genuine chain sold from "Mumaxun Ltd". Whenever you encounter any problem with the product, we will have the corresponding team to solve it for you.</b><br><br> <b>Please no hesitation send the email to us if you have any question of the product or your order, we have a professional customer service team dedicated to you.</b><br><br> <b>Perfect for 49cc to 80cc 2-Stroke Engine Motorized Bikes/Bicycle I CH15</b><br><br> <b>Offer top quality durable chain</b><br> 1. Our #415 chain, master links, and half links are available in both heavy-duty and standard-duty versions.<br> 2. Heavy-Duty #415 chain is best suited for motorized bicycles and tricycles, freight bicycles, and heavy-duty tricycles.<br> 3. Standard-Duty #415 chain is best suited for light-duty pedal powered tricycles.<br><br> <b>Note: </b><br> Our 415 Chains are considered heavy duty chains and are only compatible with forFlying Horse and for Mega Motors Bicycle Engine Kits. Most engine kit's drive sprockets will need to be modified to fit these chains, including filing the teeth down.