Specifications Hign-concerned Chemical:None is_customized:No Material:Alloy Gear Teeth:12 - 18T Freewheel Speed:1 Origin:Mainland China Components:Freewheel Name:MUQZI mountain bike bicycle flywheel Material:aluminum alloy stainless steel Color:black Specification:13T/16T/20T Net weight:about 38.3g/70.3g/88g U.S. buyer attention: The areas where the US warehouse does not deliver goods are: Hawaii, Alaska, Puerto Rico, Guam and other US overseas territories. And the military address. But you can choose ship from China. Spanish buyers attention: If your address includes following postal code please do not choose the Spanish warehouse. The zip code starts with 35/38. Overseas warehouse cannot be delivered. But you can choose ship from China MUQZI MTB Bicycle Cassette Freewheel Single Speed Mountain Bike Flywheel Sprocket Conversion Cycling Accessories Parts Feature: 1. The flywheel adopts high resistance stainless steel, its strength and hardness are twice as high as that of ordinary 316 stainless steel, and the hardness reaches 18 degrees. 2. The screws are made of stainless steel, anticorrosive and rustproof, suitable for long-term outdoor cycling. 3. The compression plate and gasket are made of 6061 aluminum alloy, which is ultra-light and corrosion resistant, maintaining strength and reducing weight at the same time. Specification: Name: MUQZI mountain bike bicycle flywheel Material: aluminum alloy + stainless steel Color: black Specification: 13T/16T/20T Package size: about 120x100x40mm/4.72*3.94*1.57in Net weight: about 38.3g/70.3g/88g Note: This flywheel is compatible with 7-10 speed cassette flywheel tower base, the chain please choose 7-10 chain to install. The mountain bike itself can buy single flywheel if it has anti-dropout, if not please buy the set of anti-dropout + flywheel. Due to the different monitor and light effect, the actual color of the item might be slightly different from the color showed on the pictures. Thank you! Please allow 1-2cm measuring deviation due to manual measurement. 1 X MTB Bike Flywheel